Make rendering timeouts work even if paint data received early

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 431 matching lines @@
     , m_flingModifier(0)
     , m_flingSourceDevice(false)
     , m_fullscreenController(FullscreenController::create(this))
     , m_showFPSCounter(false)
     , m_baseBackgroundColor(Color::white)
     , m_backgroundColorOverride(Color::transparent)
     , m_zoomFactorOverride(0)
     , m_userGestureObserved(false)
     , m_shouldDispatchFirstVisuallyNonEmptyLayout(false)
     , m_shouldDispatchFirstLayoutAfterFinishedParsing(false)
+    , m_shouldDispatchFirstPaintAfterLoad(false)
     , m_displayMode(WebDisplayModeBrowser)
     , m_elasticOverscroll(FloatSize())
 {
     Page::PageClients pageClients;
     pageClients.chromeClient = m_chromeClientImpl.get();
     pageClients.contextMenuClient = &m_contextMenuClientImpl;
     pageClients.editorClient = &m_editorClientImpl;
     pageClients.dragClient = &m_dragClientImpl;
     pageClients.spellCheckerClient = &m_spellCheckerClientImpl;
 
@@ skipping 3398 matching lines @@
 #endif
 }
 
 void WebViewImpl::didCommitLoad(bool isNewNavigation, bool isNavigationWithinPage)
 {
     if (isNewNavigation && !isNavigationWithinPage) {
         pageScaleConstraintsSet().setNeedsReset(true);
         m_pageImportanceSignals.onCommitLoad();
     }
 
+    if (m_shouldDispatchFirstPaintAfterLoad) {
+        m_shouldDispatchFirstPaintAfterLoad = false;

[dcheng, 2015/09/30 21:16:03]

Why does this dispatch the didFirstPaintAfterLoad()? There's no painting
involved here, is there?

[kenrb, 2015/09/30 21:40:41]

I've changed the name. The fact that it will queue a message to be sent with the
next paint isn't really relevant here.

+        client()->didFirstPaintAfterLoad();
+    }
+
     // Give the visual viewport's scroll layer its initial size.
     page()->frameHost().visualViewport().mainFrameDidChangeSize();
 
     // Make sure link highlight from previous page is cleared.
     m_linkHighlights.clear();
     endActiveFlingAnimation();
     m_userGestureObserved = false;
 }
 
 void WebViewImpl::documentElementAvailable(WebLocalFrameImpl* webframe)
@@ skipping 260 matching lines @@
         m_rootGraphicsLayer = nullptr;
         m_rootLayer = nullptr;
         m_rootTransformLayer = nullptr;
         // This means that we're transitioning to a new page. Suppress
         // commits until Blink generates invalidations so we don't
         // attempt to paint too early in the next page load.
         m_layerTreeView->setDeferCommits(true);
         m_layerTreeView->clearRootLayer();
         m_shouldDispatchFirstVisuallyNonEmptyLayout = true;
         m_shouldDispatchFirstLayoutAfterFinishedParsing = true;
+        m_shouldDispatchFirstPaintAfterLoad = true;
         page()->frameHost().visualViewport().clearLayersForTreeView(m_layerTreeView);
     }
 }
 
 void WebViewImpl::invalidateRect(const IntRect& rect)
 {
     if (m_layerTreeView)
         updateLayerTreeViewport();
     else if (m_client)
         m_client->didInvalidateRect(rect);
@@ skipping 292 matching lines @@
     if (m_pageColorOverlay)
         m_pageColorOverlay->update();
     if (InspectorOverlay* overlay = inspectorOverlay()) {
         PageOverlay* inspectorPageOverlay = overlay->pageOverlay();
         if (inspectorPageOverlay)
             inspectorPageOverlay->update();
     }
 }
 
 } // namespace blink