Bug 1594472 - do less work for same-document navigations, r=MattN,mconley

Updating tab
- mute state
- audio playing indicator state
- find bar state
- tab titles
- icons

is not necessary when the navigation is same-document. Avoid doing the work.

Differential Revision: https://phabricator.services.mozilla.com/D52109

--HG--
extra : moz-landing-system : lando

browser/base/content/tabbrowser.js

@@ -5857,45 +5857,50 @@
           gBrowser._tabAttrModified(this.mTab, ["busy"]);
         }
 
-        // If the browser was playing audio, we should remove the playing state.
-        if (this.mTab.hasAttribute("soundplaying") && !isSameDocument) {
-          clearTimeout(this.mTab._soundPlayingAttrRemovalTimer);
-          this.mTab._soundPlayingAttrRemovalTimer = 0;
-          this.mTab.removeAttribute("soundplaying");
-          gBrowser._tabAttrModified(this.mTab, ["soundplaying"]);
-        }
-
-        // If the browser was previously muted, we should restore the muted state.
-        if (this.mTab.hasAttribute("muted")) {
-          this.mTab.linkedBrowser.mute();
-        }
-
-        if (gBrowser.isFindBarInitialized(this.mTab)) {
-          let findBar = gBrowser.getCachedFindBar(this.mTab);
-
-          // Close the Find toolbar if we're in old-style TAF mode
-          if (findBar.findMode != findBar.FIND_NORMAL) {
-            findBar.close();
+        if (!isSameDocument) {
+          // If the browser was playing audio, we should remove the playing state.
+          if (this.mTab.hasAttribute("soundplaying")) {
+            clearTimeout(this.mTab._soundPlayingAttrRemovalTimer);
+            this.mTab._soundPlayingAttrRemovalTimer = 0;
+            this.mTab.removeAttribute("soundplaying");
+            gBrowser._tabAttrModified(this.mTab, ["soundplaying"]);
           }
-        }
 
-        if (!isReload) {
-          gBrowser.setTabTitle(this.mTab);
-        }
+          // If the browser was previously muted, we should restore the muted state.
+          if (this.mTab.hasAttribute("muted")) {
+            this.mTab.linkedBrowser.mute();
+          }
 
-        // Don't clear the favicon if this tab is in the pending
-        // state, as SessionStore will have set the icon for us even
-        // though we're pointed at an about:blank. Also don't clear it
-        // if onLocationChange was triggered by a pushState or a
-        // replaceState (bug 550565) or a hash change (bug 408415).
-        if (
-          !this.mTab.hasAttribute("pending") &&
-          aWebProgress.isLoadingDocument &&
-          !isSameDocument
-        ) {
-          // Removing the tab's image here causes flickering, wait until the load
-          // is complete.
-          this.mBrowser.mIconURL = null;
+          if (gBrowser.isFindBarInitialized(this.mTab)) {
+            let findBar = gBrowser.getCachedFindBar(this.mTab);
+
+            // Close the Find toolbar if we're in old-style TAF mode
+            if (findBar.findMode != findBar.FIND_NORMAL) {
+              findBar.close();
+            }
+          }
+
+          // Note that we're not updating for same-document loads, despite
+          // the `title` argument to `history.pushState/replaceState`. For
+          // context, see https://bugzilla.mozilla.org/show_bug.cgi?id=585653
+          // and https://github.com/whatwg/html/issues/2174
+          if (!isReload) {
+            gBrowser.setTabTitle(this.mTab);
+          }
+
+          // Don't clear the favicon if this tab is in the pending
+          // state, as SessionStore will have set the icon for us even
+          // though we're pointed at an about:blank. Also don't clear it
+          // if onLocationChange was triggered by a pushState or a
+          // replaceState (bug 550565) or a hash change (bug 408415).
+          if (
+            !this.mTab.hasAttribute("pending") &&
+            aWebProgress.isLoadingDocument
+          ) {
+            // Removing the tab's image here causes flickering, wait until the
+            // load is complete.
+            this.mBrowser.mIconURL = null;
+          }
         }
 
         let userContextId = this.mBrowser.getAttribute("usercontextid") || 0;