Bug 1687618 - Remove browser.cache.cache_isolation r=necko-reviewers,dragana

Differential Revision: https://phabricator.services.mozilla.com/D102711

dom/security/test/general/test_cache_split.html

@@ -84,8 +84,7 @@
                     steps: [[SAME_ORIGIN, 1], [SAME_ORIGIN, 1], [CROSS_ORIGIN, 2]],
                     prefs: {
                         set: [
-                            ["browser.cache.cache_isolation", true],
-                            ["privacy.partition.network_state", false]
+                            ["privacy.partition.network_state", true]
                         ],
                     },
                 })
@@ -99,7 +98,6 @@
                     steps: [[SAME_ORIGIN, 1], [SAME_ORIGIN, 1], [CROSS_ORIGIN, 1]],
                     prefs: {
                         set: [
-                            ["browser.cache.cache_isolation", false],
                             ["privacy.partition.network_state", false]
                         ],
                     },
@@ -114,7 +112,6 @@
                     prefs: {
                         set: [
                             ["privacy.firstparty.isolate", true],
-                            ["browser.cache.cache_isolation", true],
                             ["privacy.partition.network_state", false],
                         ],
                     },
@@ -130,9 +127,8 @@
                         prefs: {
                             set: [
                                 ["privacy.firstparty.isolate", false],
-                                ["browser.cache.cache_isolation", true],
                                 ["network.cookie.cookieBehavior", i],
-                                ["privacy.partition.network_state", false],
+                                ["privacy.partition.network_state", true],
                             ],
                         },
                     })
@@ -146,7 +142,6 @@
                     prefs: {
                         set: [
                           ["privacy.firstparty.isolate", true],
-                          ["browser.cache.cache_isolation", false],
                           ["privacy.partition.network_state", false],
                         ],
                     },

modules/libpref/init/StaticPrefList.yaml

@@ -775,12 +775,6 @@
   value: 256000
   mirror: always
 
-# Enable/Disable Origin based cache isolation
-- name: browser.cache.cache_isolation
-  type: RelaxedAtomicBool
-  value: false
-  mirror: always
-
 # -1 = determine dynamically, 0 = none, n = memory capacity in kilobytes.
 - name: browser.cache.memory.capacity
   type: RelaxedAtomicInt32

netwerk/protocol/http/nsHttpChannel.cpp

@@ -3657,15 +3657,16 @@ nsresult nsHttpChannel::OpenCacheEntry(bool isHttps) {
 }
 
 bool nsHttpChannel::IsIsolated() {
-  if (LoadHasBeenIsolatedChecked()) {
-    return LoadIsIsolated();
-  }
-  StoreIsIsolated(
-      StaticPrefs::browser_cache_cache_isolation() ||
-      (IsThirdPartyTrackingResource() &&
-       !ContentBlocking::ShouldAllowAccessFor(this, mURI, nullptr)));
-  StoreHasBeenIsolatedChecked(true);
-  return LoadIsIsolated();
+  return false;
+  // if (LoadHasBeenIsolatedChecked()) {
+  //   return LoadIsIsolated();
+  // }
+  // StoreIsIsolated(
+  //     StaticPrefs::browser_cache_cache_isolation() ||
+  //     (IsThirdPartyTrackingResource() &&
+  //      !ContentBlocking::ShouldAllowAccessFor(this, mURI, nullptr)));
+  // StoreHasBeenIsolatedChecked(true);
+  // return LoadIsIsolated();
 }
 
 const nsCString& nsHttpChannel::GetTopWindowOrigin() {
@@ -3815,16 +3816,6 @@ nsresult nsHttpChannel::OpenCacheEntryInternal(
     mCacheIdExtension.Append("HEAD");
   }
 
-  if (IsIsolated()) {
-    auto& topWindowOrigin = GetTopWindowOrigin();
-    if (topWindowOrigin.IsEmpty()) {
-      return NS_ERROR_FAILURE;
-    }
-
-    mCacheIdExtension.Append("-unique:");
-    mCacheIdExtension.Append(topWindowOrigin);
-  }
-
   mCacheOpenWithPriority = cacheEntryOpenFlags & nsICacheStorage::OPEN_PRIORITY;
   mCacheQueueSizeWhenOpen =
       CacheStorageService::CacheQueueSize(mCacheOpenWithPriority);

netwerk/protocol/http/nsHttpChannel.h

@@ -720,14 +720,6 @@ class nsHttpChannel final : public HttpBaseChannel,
     // Used to suspend any newly created pumps in mCallOnResume handler.
     (uint32_t, AsyncResumePending, 1),
 
-    // True only when we have checked whether this channel has been isolated for
-    // anti-tracking purposes.
-    (uint32_t, HasBeenIsolatedChecked, 1),
-    // True only when we have determined this channel should be isolated for
-    // anti-tracking purposes.  Can never ben true unless HasBeenIsolatedChecked
-    // is true.
-    (uint32_t, IsIsolated, 1),
-
     // True only when we have computed the value of the top window origin.
     (uint32_t, TopWindowOriginComputed, 1),