Backed out changeset f3fe6cc42791 (bug 1809094) for bc failures on browser_ext_tabs_autoDiscardable.js.

browser/base/content/tabbrowser-tab.js

@@ -154,15 +154,6 @@
       gBrowser._tabAttrModified(this, ["attention"]);
     }
 
-    set undiscardable(val) {
-      if (val == this.hasAttribute("undiscardable")) {
-        return;
-      }
-
-      this.toggleAttribute("undiscardable", val);
-      gBrowser._tabAttrModified(this, ["undiscardable"]);
-    }
-
     set _visuallySelected(val) {
       if (val == (this.getAttribute("visuallyselected") == "true")) {
         return;
@@ -233,10 +224,6 @@
       return this.getAttribute("activemedia-blocked") == "true";
     }
 
-    get undiscardable() {
-      return this.hasAttribute("undiscardable");
-    }
-
     get isEmpty() {
       // Determines if a tab is "empty", usually used in the context of determining
       // if it's ok to close the tab.

browser/base/content/tabbrowser.js

@@ -4547,10 +4547,6 @@
         }
         modifiedAttrs.push("muted");
       }
-      if (aOtherTab.hasAttribute("undiscardable")) {
-        aOurTab.setAttribute("undiscardable", "true");
-        modifiedAttrs.push("undiscardable");
-      }
       if (aOtherTab.hasAttribute("soundplaying")) {
         aOurTab.setAttribute("soundplaying", "true");
         modifiedAttrs.push("soundplaying");

browser/components/extensions/parent/ext-browser.js

@@ -747,10 +747,6 @@ class Tab extends TabBase {
     return this.nativeTab.soundPlaying;
   }
 
-  get autoDiscardable() {
-    return !this.nativeTab.undiscardable;
-  }
-
   get browser() {
     return this.nativeTab.linkedBrowser;
   }

browser/components/extensions/parent/ext-tabs.js

@@ -150,12 +150,10 @@ const allAttrs = new Set([
   "mutedInfo",
   "sharingState",
   "title",
-  "autoDiscardable",
 ]);
 const allProperties = new Set([
   "attention",
   "audible",
-  "autoDiscardable",
   "discarded",
   "favIconUrl",
   "hidden",
@@ -421,12 +419,6 @@ this.tabs = class extends ExtensionAPIPersistent {
           ) {
             needed.push("audible");
           }
-          if (
-            changed.includes("undiscardable") &&
-            filter.properties.has("autoDiscardable")
-          ) {
-            needed.push("autoDiscardable");
-          }
           if (changed.includes("label") && filter.properties.has("title")) {
             needed.push("title");
           }
@@ -906,9 +898,6 @@ this.tabs = class extends ExtensionAPIPersistent {
           if (updateProperties.active) {
             tabbrowser.selectedTab = nativeTab;
           }
-          if (updateProperties.autoDiscardable !== null) {
-            nativeTab.undiscardable = !updateProperties.autoDiscardable;
-          }
           if (updateProperties.highlighted !== null) {
             if (updateProperties.highlighted) {
               if (!nativeTab.selected && !nativeTab.multiselected) {

browser/components/extensions/schemas/tabs.json

@@ -139,11 +139,6 @@
             "optional": true,
             "description": "Whether the tab has produced sound over the past couple of seconds (but it might not be heard if also muted). Equivalent to whether the speaker audio indicator is showing."
           },
-          "autoDiscardable": {
-            "type": "boolean",
-            "optional": true,
-            "description": "Whether the tab can be discarded automatically by the browser when resources are low."
-          },
           "mutedInfo": {
             "$ref": "MutedInfo",
             "optional": true,
@@ -430,7 +425,6 @@
         "enum": [
           "attention",
           "audible",
-          "autoDiscardable",
           "discarded",
           "favIconUrl",
           "hidden",
@@ -747,11 +741,6 @@
                 "optional": true,
                 "description": "Whether the tabs are audible."
               },
-              "autoDiscardable": {
-                "type": "boolean",
-                "optional": true,
-                "description": "Whether the tab can be discarded automatically by the browser when resources are low."
-              },
               "muted": {
                 "type": "boolean",
                 "optional": true,
@@ -949,11 +938,6 @@
                 "optional": true,
                 "description": "Whether the tab should be active. Does not affect whether the window is focused (see $(ref:windows.update))."
               },
-              "autoDiscardable": {
-                "type": "boolean",
-                "optional": true,
-                "description": "Whether the tab can be discarded automatically by the browser when resources are low."
-              },
               "highlighted": {
                 "type": "boolean",
                 "optional": true,
@@ -1631,11 +1615,6 @@
                 "optional": true,
                 "description": "The tab's new audible state."
               },
-              "autoDiscardable": {
-                "type": "boolean",
-                "optional": true,
-                "description": "The tab's new autoDiscardable state."
-              },
               "discarded": {
                 "type": "boolean",
                 "optional": true,

browser/components/extensions/test/browser/browser.ini

@@ -296,7 +296,6 @@ skip-if =
 [browser_ext_tabs_attention.js]
 https_first_disabled = true
 [browser_ext_tabs_audio.js]
-[browser_ext_tabs_autoDiscardable.js]
 [browser_ext_tabs_containerIsolation.js]
 https_first_disabled = true
 [browser_ext_tabs_cookieStoreId.js]

browser/components/extensions/test/browser/browser_ext_tabs_autoDiscardable.js

@@ -1,177 +0,0 @@
-"use strict";
-
-add_task(async function test_autoDiscardable() {
-  let files = {
-    "schema.json": JSON.stringify([
-      {
-        namespace: "experiments",
-        functions: [
-          {
-            name: "unload",
-            type: "function",
-            async: "callback",
-            description:
-              "Unload the least recently used tab using Firefox's built-in tab unloader mechanism",
-            parameters: [],
-          },
-        ],
-      },
-    ]),
-    "parent.js": () => {
-      const { TabUnloader } = ChromeUtils.importESModule(
-        "resource:///modules/TabUnloader.sys.mjs"
-      );
-      const { ExtensionError } = ExtensionUtils;
-      this.experiments = class extends ExtensionAPI {
-        getAPI(context) {
-          return {
-            experiments: {
-              async unload() {
-                try {
-                  await TabUnloader.unloadLeastRecentlyUsedTab(null);
-                } catch (error) {
-                  // We need to do this, otherwise failures won't bubble up to the test properly.
-                  throw ExtensionError(error);
-                }
-              },
-            },
-          };
-        }
-      };
-    },
-  };
-
-  async function background() {
-    let firstTab = await browser.tabs.create({
-      active: false,
-      url: "https://example.org/",
-    });
-
-    // Make sure setting and getting works properly
-    browser.test.assertTrue(
-      firstTab.autoDiscardable,
-      "autoDiscardable should always be true by default"
-    );
-    let result = await browser.tabs.update(firstTab.id, {
-      autoDiscardable: false,
-    });
-    browser.test.assertFalse(
-      result.autoDiscardable,
-      "autoDiscardable should be false after setting it as such"
-    );
-    result = await browser.tabs.update(firstTab.id, {
-      autoDiscardable: true,
-    });
-    browser.test.assertTrue(
-      result.autoDiscardable,
-      "autoDiscardable should be true after setting it as such"
-    );
-    result = await browser.tabs.update(firstTab.id, {
-      autoDiscardable: false,
-    });
-    browser.test.assertFalse(
-      result.autoDiscardable,
-      "autoDiscardable should be false after setting it as such"
-    );
-
-    // Make sure the tab can't be unloaded when autoDiscardable is false
-    await browser.experiments.unload();
-    result = await browser.tabs.get(firstTab.id);
-    browser.test.assertFalse(
-      result.discarded,
-      "Tab should not unload when autoDiscardable is false"
-    );
-
-    // Make sure the tab CAN be unloaded when autoDiscardable is true
-    await browser.tabs.update(firstTab.id, {
-      autoDiscardable: true,
-    });
-    await browser.experiments.unload();
-    result = await browser.tabs.get(firstTab.id);
-    browser.test.assertTrue(
-      result.discarded,
-      "Tab should unload when autoDiscardable is true"
-    );
-
-    // Make sure filtering for discardable tabs works properly
-    result = await browser.tabs.query({ autoDiscardable: true });
-    browser.test.assertEq(
-      2,
-      result.length,
-      "tabs.query should return 2 when autoDiscardable is true "
-    );
-    await browser.tabs.update(firstTab.id, {
-      autoDiscardable: false,
-    });
-    result = await browser.tabs.query({ autoDiscardable: true });
-    browser.test.assertEq(
-      1,
-      result.length,
-      "tabs.query should return 1 when autoDiscardable is false"
-    );
-
-    let onUpdatedPromise = {};
-    onUpdatedPromise.promise = new Promise(
-      resolve => (onUpdatedPromise.resolve = resolve)
-    );
-
-    // Make sure onUpdated works
-    async function testOnUpdatedEvent(autoDiscardable) {
-      browser.test.log(`Testing autoDiscardable = ${autoDiscardable}`);
-      let onUpdated;
-      let promise = new Promise(resolve => {
-        onUpdated = (tabId, changeInfo, tabInfo) => {
-          browser.test.assertEq(
-            firstTab.id,
-            tabId,
-            "The updated tab's ID should match the correct tab"
-          );
-          browser.test.assertDeepEq(
-            { autoDiscardable },
-            changeInfo,
-            "The updated tab's changeInfo should be correct"
-          );
-          browser.test.assertEq(
-            tabInfo.autoDiscardable,
-            autoDiscardable,
-            "The updated tab's tabInfo should be correct"
-          );
-          resolve();
-        };
-      });
-      browser.tabs.onUpdated.addListener(onUpdated, {
-        properties: ["autoDiscardable"],
-      });
-      await browser.tabs.update(firstTab.id, { autoDiscardable });
-      await promise;
-      browser.tabs.onUpdated.removeListener(onUpdated);
-    }
-
-    await testOnUpdatedEvent(true);
-    await testOnUpdatedEvent(false);
-
-    await browser.tabs.remove(firstTab.id); // Cleanup
-    browser.test.notifyPass("autoDiscardable");
-  }
-  let extension = ExtensionTestUtils.loadExtension({
-    isPrivileged: true,
-    manifest: {
-      permissions: ["tabs"],
-      experiment_apis: {
-        experiments: {
-          schema: "schema.json",
-          parent: {
-            scopes: ["addon_parent"],
-            script: "parent.js",
-            paths: [["experiments"]],
-          },
-        },
-      },
-    },
-    background,
-    files,
-  });
-  await extension.startup();
-  await extension.awaitFinish("autoDiscardable");
-  await extension.unload();
-});

browser/modules/TabUnloader.sys.mjs

@@ -52,7 +52,7 @@ let CRITERIA_WEIGHT = 1;
  */
 let DefaultTabUnloaderMethods = {
   isNonDiscardable(tab, weight) {
-    if (tab.undiscardable || tab.selected) {
+    if (tab.selected) {
       return weight;
     }
 

mobile/android/components/extensions/ext-android.js

@@ -391,12 +391,6 @@ class Tab extends TabBase {
     return false;
   }
 
-  get autoDiscardable() {
-    // This property reflects whether the browser is allowed to auto-discard.
-    // Since extensions cannot do so on Android, we return true here.
-    return true;
-  }
-
   get sharingState() {
     return {
       screen: undefined,

mobile/android/components/extensions/schemas/tabs.json

@@ -140,11 +140,6 @@
             "optional": true,
             "description": "Whether the tab has produced sound over the past couple of seconds (but it might not be heard if also muted). Equivalent to whether the speaker audio indicator is showing."
           },
-          "autoDiscardable": {
-            "type": "boolean",
-            "optional": true,
-            "description": "Whether the tab can be discarded automatically by the browser when resources are low."
-          },
           "mutedInfo": {
             "$ref": "MutedInfo",
             "optional": true,

mobile/android/components/extensions/test/mochitest/mochitest.ini

@@ -18,7 +18,6 @@ prefs =
 [test_ext_all_apis.html]
 [test_ext_downloads_event_page.html]
 [test_ext_tab_runtimeConnect.html]
-[test_ext_tabs_autoDiscardable.html]
 [test_ext_tabs_create.html]
 [test_ext_tabs_events.html]
 skip-if =

mobile/android/components/extensions/test/mochitest/test_ext_tabs_autoDiscardable.html

@@ -1,48 +0,0 @@
-<!DOCTYPE HTML>
-<html>
-
-<head>
-  <meta charset="utf-8">
-  <title>autoDiscardable test</title>
-  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
-  <script type="text/javascript" src="/tests/SimpleTest/ExtensionTestUtils.js"></script>
-  <script type="text/javascript" src="head.js"></script>
-  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
-</head>
-
-<body>
-  <script type="text/javascript">
-    "use strict";
-
-    add_task(async function () {
-      async function background() {
-        const tab = await browser.tabs.create({ title: "Test Tab" });
-        browser.test.assertTrue(
-          tab.autoDiscardable,
-          "autoDiscardable should be true on Android"
-        );
-        browser.test.assertThrows(
-          () => browser.tabs.query({ autoDiscardable: true }),
-          "tabs.query with autoDiscardable should error out on Android"
-        );
-        browser.test.assertThrows(
-          () => browser.tabs.update(tab.id, { autoDiscardable: true }),
-          "tabs.update with autoDiscardable should error out on Android"
-        );
-        browser.test.notifyPass("tab.autoDiscardable");
-      }
-      const extension = ExtensionTestUtils.loadExtension({
-        manifest: {
-          permissions: ["tabs"],
-          background,
-        },
-      });
-      await extension.startup();
-      await extension.awaitFinish("tab.autoDiscardable");
-      await extension.unload();
-    });
-  </script>
-
-</body>
-
-</html>

toolkit/components/extensions/parent/ext-tabs-base.js

@@ -285,16 +285,6 @@ class TabBase {
     throw new Error("Not implemented");
   }
 
-  /**
-   * @property {boolean} autoDiscardable
-   *        Returns true if the tab can be discarded on memory pressure, false otherwise.
-   *        @readonly
-   *        @abstract
-   */
-  get autoDiscardable() {
-    throw new Error("Not implemented");
-  }
-
   /**
    * @property {XULElement} browser
    *        Returns the XUL browser for the given tab.
@@ -525,8 +515,6 @@ class TabBase {
    *        Matches against the exact value of the tab's `active` attribute.
    * @param {boolean} [queryInfo.audible]
    *        Matches against the exact value of the tab's `audible` attribute.
-   * @param {boolean} [queryInfo.autoDiscardable]
-   *        Matches against the exact value of the tab's `autoDiscardable` attribute.
    * @param {string} [queryInfo.cookieStoreId]
    *        Matches against the exact value of the tab's `cookieStoreId` attribute.
    * @param {boolean} [queryInfo.discarded]
@@ -564,7 +552,6 @@ class TabBase {
     const PROPS = [
       "active",
       "audible",
-      "autoDiscardable",
       "discarded",
       "hidden",
       "highlighted",
@@ -650,7 +637,6 @@ class TabBase {
       height: this.height,
       lastAccessed: this.lastAccessed,
       audible: this.audible,
-      autoDiscardable: this.autoDiscardable,
       mutedInfo: this.mutedInfo,
       isArticle: this.isArticle,
       isInReaderMode: this.isInReaderMode,