Insert pinch zoom virtual viewport layers to graphics layer tree.

Source/WebKit/chromium/src/WebViewImpl.cpp

Index: Source/WebKit/chromium/src/WebViewImpl.cpp
diff --git a/Source/WebKit/chromium/src/WebViewImpl.cpp b/Source/WebKit/chromium/src/WebViewImpl.cpp
index 8792a6f93b56771340581b347dc000a3592e0af4..c06dc5eb065e23798ca1021a9eebd7365dffbb3d 100644
--- a/Source/WebKit/chromium/src/WebViewImpl.cpp
+++ b/Source/WebKit/chromium/src/WebViewImpl.cpp
@@ -57,6 +57,7 @@
 #include "HTMLNames.h"
 #include "LinkHighlight.h"
 #include "PageWidgetDelegate.h"
+#include "PinchViewports.h"
 #include "PopupContainer.h"
 #include "PrerendererClientImpl.h"
 #include "SpeechInputClientImpl.h"
@@ -1611,8 +1612,11 @@ void WebViewImpl::resize(const WebSize& newSize)
         agentPrivate->webViewResized(newSize);
     if (!agentPrivate || !agentPrivate->metricsOverridden()) {
         WebFrameImpl* webFrame = mainFrameImpl();
-        if (webFrame->frameView())
+        if (webFrame->frameView()) {
             webFrame->frameView()->resize(m_size);
+            if (m_pinchViewports)
+                m_pinchViewports->setViewportSize(FloatSize(m_size.width, m_size.height));
+        }
     }
 
     if (settings()->viewportEnabled()) {
@@ -3806,11 +3810,28 @@ void WebViewImpl::setRootGraphicsLayer(GraphicsLayer* layer)
 {
     suppressInvalidations(true);
 
-    m_rootGraphicsLayer = layer;
-    m_rootLayer = layer ? layer->platformLayer() : 0;
+    if (page()->settings()->pinchVirtualViewportEnabled() && !m_pinchViewports)
+        m_pinchViewports = PinchViewports::create(this);
+
+    if (m_pinchViewports) {
+        m_pinchViewports->setOverflowControlsHostLayer(layer);
+        if (layer) {
+            m_rootGraphicsLayer = m_pinchViewports->rootGraphicsLayer();
+            m_rootLayer = m_pinchViewports->rootGraphicsLayer()->platformLayer();
+        } else {
+            m_rootGraphicsLayer = 0;
+            m_rootLayer = 0;
+        }
+    } else {
+        m_rootGraphicsLayer = layer;
+        m_rootLayer = layer ? layer->platformLayer() : 0;
+    }
+
 
     setIsAcceleratedCompositingActive(layer);
 
+    // FIXME: We also need to tell the layer tree about the pinchViewport layers
+    // in a follow-on CL.
     if (m_layerTreeView) {
         if (m_rootLayer)
             m_layerTreeView->setRootLayer(*m_rootLayer);
@@ -3845,6 +3866,13 @@ WebCore::GraphicsLayerFactory* WebViewImpl::graphicsLayerFactory() const
     return m_graphicsLayerFactory.get();
 }
 
+WebCore::RenderLayerCompositor* WebViewImpl::compositor() const
+{
+    Document* document = page()->mainFrame()->document();

[enne (OOO), 2013/06/13 22:45:07]

Can any of these things be NULL?

[wjmaclean, 2013/06/14 15:54:16]

Yes, we should put in checks. I'm not sure what the rules are regarding whether
mainFrame() ever has a null document(), or whether those rules could ever
change, so I'll just exhaustively check them.

Done.

+    RenderView* renderView = document->renderView();
+    return renderView->compositor();
+}
+
 void WebViewImpl::registerForAnimations(WebLayer* layer)
 {
     if (m_layerTreeView)