Fix page zoom to be frame-centric for out-of-process frames.

third_party/WebKit/Source/web/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 3032 matching lines @@
     // TODO(alexmos): Pass in proper with sourceCapabilities.
     page()->focusController().advanceFocusAcrossFrames(
         type, toWebRemoteFrameImpl(from)->frame(), toWebLocalFrameImpl(to)->frame());
 }
 
 double WebViewImpl::zoomLevel()
 {
     return m_zoomLevel;
 }
 
-double WebViewImpl::setZoomLevel(double zoomLevel)
+void WebViewImpl::propagateZoomToLocalFrameRoots(Frame* frame)
 {
-    if (zoomLevel < m_minimumZoomLevel)
-        m_zoomLevel = m_minimumZoomLevel;
-    else if (zoomLevel > m_maximumZoomLevel)
-        m_zoomLevel = m_maximumZoomLevel;
-    else
-        m_zoomLevel = zoomLevel;
+    if (frame->isRemoteFrame()) {
+        for (Frame* child = frame->tree().firstChild(); child; child = child->tree().nextSibling())
+            propagateZoomToLocalFrameRoots(child);

[alexmos, 2016/04/07 23:48:08]

Hmm, what if you have a A-B-A scenario, and you send the zoom update to A's
process?  It doesn't look like this will ever reach the grandchild, since the
iteration in LocalFrame::setPageAndTextZoomFactors ignores remote children.

[wjmaclean, 2016/04/08 20:13:29]

The Zoom update will be sent to both A's and B's processes. But you're right
this will miss the grandchild.

Done.

+        return;
+    }
 
-    // TODO(nasko): Setting zoom level needs to be refactored to support
-    // out-of-process iframes. See https://crbug.com/528407.
-    if (mainFrame()->isWebRemoteFrame())
-        return m_zoomLevel;
+    ASSERT(frame->isLocalRoot());

[bokan, 2016/04/07 22:57:12]

Blink recently switched ASSERTs to DCHECKs.

[wjmaclean, 2016/04/08 20:13:29]

Done.

+    LocalFrame* localFrame = toLocalFrame(frame);
 
-    LocalFrame* frame = mainFrameImpl()->frame();
-    if (!WebLocalFrameImpl::pluginContainerFromFrame(frame)) {
+    if (!WebLocalFrameImpl::pluginContainerFromFrame(localFrame)) {
         float zoomFactor = m_zoomFactorOverride ? m_zoomFactorOverride : static_cast<float>(zoomLevelToZoomFactor(m_zoomLevel));
         if (m_zoomFactorForDeviceScaleFactor) {
             if (m_compositorDeviceScaleFactorOverride) {
                 // Adjust the page's DSF so that DevicePixelRatio becomes m_zoomFactorForDeviceScaleFactor.
                 page()->setDeviceScaleFactor(m_zoomFactorForDeviceScaleFactor / m_compositorDeviceScaleFactorOverride);
                 zoomFactor *= m_compositorDeviceScaleFactorOverride;
             } else {
                 page()->setDeviceScaleFactor(1.f);
                 zoomFactor *= m_zoomFactorForDeviceScaleFactor;
             }
         }
-        frame->setPageZoomFactor(zoomFactor);
+        localFrame->setPageZoomFactor(zoomFactor);
     }
+}
+
+double WebViewImpl::setZoomLevel(double zoomLevel)
+{
+    if (zoomLevel < m_minimumZoomLevel)
+        m_zoomLevel = m_minimumZoomLevel;
+    else if (zoomLevel > m_maximumZoomLevel)
+        m_zoomLevel = m_maximumZoomLevel;
+    else
+        m_zoomLevel = zoomLevel;
+
+    propagateZoomToLocalFrameRoots(m_page->mainFrame());
 
     return m_zoomLevel;
 }
 
 void WebViewImpl::zoomLimitsChanged(double minimumZoomLevel,
                                     double maximumZoomLevel)
 {
     m_minimumZoomLevel = minimumZoomLevel;
     m_maximumZoomLevel = maximumZoomLevel;
     m_client->zoomLimitsChanged(m_minimumZoomLevel, m_maximumZoomLevel);
@@ skipping 1500 matching lines @@
 {
     // TODO(oshima): Investigate if this should return the ScreenInfo's scale factor rather than
     // page's scale factor, which can be 1 in use-zoom-for-dsf mode.
     if (!page())
         return 1;
 
     return page()->deviceScaleFactor();
 }
 
 } // namespace blink