Bug 709492 - Part 4: Hide the page when navigating, and expose it when the new page appears. r=kats

mobile/android/base/GeckoApp.java

@@ -616,7 +616,10 @@ abstract public class GeckoApp
                     mLastTitle == lastHistoryEntry.mTitle)
                     return;
 
-                mLastViewport = mSoftwareLayerClient.getGeckoViewportMetrics().toJSON();
+                ViewportMetrics viewportMetrics = mSoftwareLayerClient.getGeckoViewportMetrics();
+                if (viewportMetrics != null)
+                    mLastViewport = viewportMetrics.toJSON();
+
                 mLastUri = lastHistoryEntry.mUri;
                 mLastTitle = lastHistoryEntry.mTitle;
                 Bitmap bitmap = mSoftwareLayerClient.getBitmap();

mobile/android/base/gfx/GeckoSoftwareLayerClient.java

@@ -140,7 +140,8 @@ public class GeckoSoftwareLayerClient extends LayerClient implements GeckoEventL
             layerController.setViewportMetrics(mGeckoViewport);
         }
 
-        GeckoAppShell.registerGeckoEventListener("Viewport:Update", this);
+        GeckoAppShell.registerGeckoEventListener("Viewport:Expose", this);
+        GeckoAppShell.registerGeckoEventListener("Viewport:UpdateAndDraw", this);
         GeckoAppShell.registerGeckoEventListener("Viewport:UpdateLater", this);
     }
 
@@ -340,19 +341,15 @@ public class GeckoSoftwareLayerClient extends LayerClient implements GeckoEventL
     }
 
     public void handleMessage(String event, JSONObject message) {
-        if ("Viewport:Update".equals(event)) {
-            beginTransaction(mTileLayer);
-            try {
-                updateViewport(message.getString("viewport"), false);
-            } catch (JSONException e) {
-                Log.e(LOGTAG, "Unable to update viewport", e);
-            } finally {
-                endTransaction(mTileLayer);
-            }
+        if ("Viewport:Expose".equals(event)) {
+            GeckoAppShell.sendEventToGecko(new GeckoEvent(GeckoEvent.EXPOSE));
+        } else if ("Viewport:UpdateAndDraw".equals(event)) {
+            mUpdateViewportOnEndDraw = true;
+
+            // Redraw everything.
+            Rect rect = new Rect(0, 0, mBufferSize.width, mBufferSize.height);
+            GeckoAppShell.sendEventToGecko(new GeckoEvent(GeckoEvent.DRAW, rect));
         } else if ("Viewport:UpdateLater".equals(event)) {
-            if (!mTileLayer.inTransaction()) {
-                Log.e(LOGTAG, "Viewport:UpdateLater called while not in transaction. You should be using Viewport:Update instead!");
-            }
             mUpdateViewportOnEndDraw = true;
         }
     }

mobile/android/base/ui/PanZoomController.java

@@ -264,7 +264,10 @@ public class PanZoomController
             // the screen orientation changed) so abort it and start a new one to
             // ensure the viewport doesn't contain out-of-bounds areas
         case NOTHING:
-            bounce();
+            // Don't do animations here; they're distracting and can cause flashes on page
+            // transitions.
+            mController.setViewportMetrics(getValidViewportMetrics());
+            mController.notifyLayerClientOfGeometryChange();
             break;
         }
     }

mobile/android/chrome/content/browser.js

@@ -200,6 +200,7 @@ var BrowserApp = {
     Services.obs.addObserver(this, "Viewport:Change", false);
     Services.obs.addObserver(this, "AgentMode:Change", false);
     Services.obs.addObserver(this, "SearchEngines:Get", false);
+    Services.obs.addObserver(this, "document-shown", false);
 
     function showFullScreenWarning() {
       NativeWindow.toast.show(Strings.browser.GetStringFromName("alertFullScreenToast"), "short");
@@ -715,6 +716,20 @@ var BrowserApp = {
       ViewportHandler.onResize();
     } else if (aTopic == "SearchEngines:Get") {
       this.getSearchEngines();
+    } else if (aTopic == "document-shown") {
+      let tab = this.selectedTab;
+      if (tab.browser.contentDocument != aSubject) {
+        return;
+      }
+
+      ViewportHandler.updateMetadata(tab);
+
+      // Unsuppress drawing unless the page was being thawed from the bfcache (which is an atomic
+      // operation, so there is no drawing to suppress).
+      if (tab.suppressDrawing) {
+        tab.sendExposeEvent();
+        tab.suppressDrawing = false;
+      }
     }
   },
 
@@ -1194,6 +1209,12 @@ Tab.prototype = {
     this.browser.addEventListener("PluginClickToPlay", this, true);
     this.browser.addEventListener("pagehide", this, true);
 
+    let chromeEventHandler = this.browser.contentWindow.QueryInterface(Ci.nsIInterfaceRequestor)
+                                                       .getInterface(Ci.nsIWebNavigation)
+                                                       .QueryInterface(Ci.nsIDocShell)
+                                                       .chromeEventHandler;
+    chromeEventHandler.addEventListener("DOMWindowCreated", this, false);
+
     Services.obs.addObserver(this, "http-on-modify-request", false);
 
     if (!aParams.delayLoad) {
@@ -1403,8 +1424,7 @@ Tab.prototype = {
       return;
     sendMessageToJava({
       gecko: {
-        type: "Viewport:Update",
-        viewport: JSON.stringify(this.viewport)
+        type: "Viewport:UpdateAndDraw"
       }
     });
   },
@@ -1547,6 +1567,18 @@ Tab.prototype = {
         }
         break;
       }
+
+      case "DOMWindowCreated": {
+        // Conveniently, this call to getBrowserForDocument() will return null if the document is
+        // not the top-level content document of the browser.
+        let browser = BrowserApp.getBrowserForDocument(aEvent.originalTarget);
+        if (!browser)
+          break;
+
+        let tab = BrowserApp.getTabForBrowser(browser);
+        tab.suppressDrawing = true;
+        break;
+      }
     }
   },
 
@@ -1806,6 +1838,16 @@ Tab.prototype = {
     }
   },
 
+  sendExposeEvent: function() {
+    // Now that the document is actually on the screen, send an expose event.
+    this._timer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
+    sendMessageToJava({
+      gecko: {
+        type: "Viewport:Expose"
+      }
+    });
+  },
+
   QueryInterface: XPCOMUtils.generateQI([
     Ci.nsIWebProgressListener,
     Ci.nsISHistoryListener,