bug 719359 - Pageload thumbnails for sites with <meta viewport=width=n> do not cover entire thumbnail box in about:home r=mfinkle

mobile/android/chrome/content/browser.js

@@ -1011,13 +1011,9 @@ var BrowserApp = {
   },
 
   // nsIAndroidBrowserApp
-  getWindowForTab: function(tabId) {
-      let tab = this.getTabForId(tabId);
-      if (!tab.browser)
-	  return null;
-      return tab.browser.contentWindow;
+  getBrowserTab: function(tabId) {
+    return this.getTabForId(tabId);
   }
-
 };
 
 var NativeWindow = {
@@ -2253,11 +2249,23 @@ Tab.prototype = {
     }
   },
 
+  // nsIBrowserTab
+  get window() {
+    if (!this.browser)
+      return null;
+    return this.browser.contentWindow;
+  },
+
+  get scale() {
+    return this.viewport.zoom;
+  },
+
   QueryInterface: XPCOMUtils.generateQI([
     Ci.nsIWebProgressListener,
     Ci.nsISHistoryListener,
     Ci.nsIObserver,
-    Ci.nsISupportsWeakReference
+    Ci.nsISupportsWeakReference,
+    Ci.nsIBrowserTab
   ])
 };
 

widget/android/AndroidBridge.cpp

@@ -1990,7 +1990,7 @@ jobject JNICALL
 Java_org_mozilla_gecko_GeckoAppShell_allocateDirectBuffer(JNIEnv *jenv, jclass, jlong size);
 
 
-nsresult AndroidBridge::TakeScreenshot(nsIDOMWindow *window, PRInt32 srcX, PRInt32 srcY, PRInt32 srcW, PRInt32 srcH, PRInt32 dstW, PRInt32 dstH, PRInt32 tabId)
+nsresult AndroidBridge::TakeScreenshot(nsIDOMWindow *window, PRInt32 srcX, PRInt32 srcY, PRInt32 srcW, PRInt32 srcH, PRInt32 dstW, PRInt32 dstH, PRInt32 tabId, float scale)
 {
     nsCOMPtr<nsPIDOMWindow> win = do_QueryInterface(window);
     if (!win)
@@ -2023,8 +2023,10 @@ nsresult AndroidBridge::TakeScreenshot(nsIDOMWindow *window, PRInt32 srcX, PRInt
         return NS_OK;
 
     void* data = jenv->GetDirectBufferAddress(buffer);
+    memset(data, 0, bufferSize);
     nsRefPtr<gfxImageSurface> surf = new gfxImageSurface(static_cast<unsigned char*>(data), nsIntSize(dstW, dstH), stride, gfxASurface::ImageFormatRGB16_565);
     nsRefPtr<gfxContext> context = new gfxContext(surf);
+    context->Scale(scale * dstW / srcW, scale * dstH / srcH);
     nsresult rv = presShell->RenderDocument(r, renderDocFlags, bgColor, context);
     NS_ENSURE_SUCCESS(rv, rv);
     AndroidBridge::AutoLocalJNIFrame jniFrame(jenv, 1);

widget/android/AndroidBridge.h

@@ -156,7 +156,7 @@ public:
 
     static void NotifyIMEChange(const PRUnichar *aText, PRUint32 aTextLen, int aStart, int aEnd, int aNewEnd);
 
-    nsresult TakeScreenshot(nsIDOMWindow *window, PRInt32 srcX, PRInt32 srcY, PRInt32 srcW, PRInt32 srcH, PRInt32 dstW, PRInt32 dstH, PRInt32 tabId);
+    nsresult TakeScreenshot(nsIDOMWindow *window, PRInt32 srcX, PRInt32 srcY, PRInt32 srcW, PRInt32 srcH, PRInt32 dstW, PRInt32 dstH, PRInt32 tabId, float scale);
 
     void AcknowledgeEventSync();
 

widget/android/nsAppShell.cpp

@@ -445,11 +445,22 @@ nsAppShell::ProcessNextNativeEvent(bool mayWait)
             break;
 
         nsCOMPtr<nsIDOMWindow> domWindow;
-        mBrowserApp->GetWindowForTab(curEvent->MetaState(), getter_AddRefs(domWindow));
+        nsCOMPtr<nsIBrowserTab> tab;
+        float scale;
+        mBrowserApp->GetBrowserTab(curEvent->MetaState(), getter_AddRefs(tab));
+        if (!tab)
+            break;
+
+        tab->GetWindow(getter_AddRefs(domWindow));
+        if (!domWindow)
+            break;
+
+        if (NS_FAILED(tab->GetScale(&scale)))
+            break;
+
         nsTArray<nsIntPoint> points = curEvent->Points();
         NS_ASSERTION(points.Length() != 2, "Screenshot event does not have enough coordinates");
-        if (domWindow)
-            bridge->TakeScreenshot(domWindow, 0, 0, points[0].x, points[0].y, points[1].x, points[1].y, curEvent->MetaState());
+        bridge->TakeScreenshot(domWindow, 0, 0, points[0].x, points[0].y, points[1].x, points[1].y, curEvent->MetaState(), scale);
         break;
     }
 

widget/android/nsIAndroidBridge.idl

@@ -12,9 +12,15 @@ interface nsIAndroidDrawMetadataProvider : nsISupports {
   boolean paintingSuppressed();
 };
 
+[scriptable, uuid(0843f3c1-043e-4c64-9d8c-091370548c05)]
+interface nsIBrowserTab : nsISupports {
+  readonly attribute nsIDOMWindow window;
+  readonly attribute float scale;
+};
+
 [scriptable, uuid(d10377b4-1c90-493a-a532-63cb3f16ee2b)]
 interface nsIAndroidBrowserApp : nsISupports {
-  nsIDOMWindow getWindowForTab(in PRInt32 tabId);
+  nsIBrowserTab getBrowserTab(in PRInt32 tabId);
 };
 
 [scriptable, uuid(7dd8441a-4f38-49b2-bd90-da69d02a96cf)]