Remove the composited path from WebViewImpl::paint().

Source/web/WebViewImpl.cpp

Index: Source/web/WebViewImpl.cpp
diff --git a/Source/web/WebViewImpl.cpp b/Source/web/WebViewImpl.cpp
index c7bd60281f12277fc42607777511075a526ae111..5c3795682cc68a9f64fae56ea60158453c45a04e 100644
--- a/Source/web/WebViewImpl.cpp
+++ b/Source/web/WebViewImpl.cpp
@@ -1767,43 +1767,38 @@ void WebViewImpl::doPixelReadbackToCanvas(WebCanvas* canvas, const IntRect& rect
     canvas->writePixels(target, rect.x(), rect.y());
 }
 
-void WebViewImpl::paint(WebCanvas* canvas, const WebRect& rect, PaintOptions option)
+void WebViewImpl::paint(WebCanvas* canvas, const WebRect& rect)

[enne (OOO), 2014/05/02 23:16:23]

I do think this needs to be split into two functions for readability at least. 
If you don't want to change the public API in this patch, could you add an
internal paintAndroid and paintNonComposited (or whatever) and just have one
#ifdef?

 {
+    // Note: This method can be called on a composited WebView on OS(ANDROID)
+    // but this will hopefully be changed once the link disambiguation feature
+    // renders using the compositor.
 #if !OS(ANDROID)
-    // ReadbackFromCompositorIfAvailable is the only option available on non-Android.
-    // Ideally, Android would always use ReadbackFromCompositorIfAvailable as well.
-    ASSERT(option == ReadbackFromCompositorIfAvailable);
+    // This should only be used when compositing is not being used for this
+    // WebView, and it is painting into the recording of its parent.
+    ASSERT(!isAcceleratedCompositingActive());
 #endif
 
-    if (option == ReadbackFromCompositorIfAvailable && isAcceleratedCompositingActive()) {
-        // If a canvas was passed in, we use it to grab a copy of the
-        // freshly-rendered pixels.
-        if (canvas) {
-            // Clip rect to the confines of the rootLayerTexture.
-            IntRect resizeRect(rect);
-            resizeRect.intersect(IntRect(IntPoint(0, 0), m_layerTreeView->deviceViewportSize()));
-            doPixelReadbackToCanvas(canvas, resizeRect);
-        }
-    } else {
-        FrameView* view = page()->mainFrame()->view();
-        PaintBehavior oldPaintBehavior = view->paintBehavior();
-        if (isAcceleratedCompositingActive()) {
-            ASSERT(option == ForceSoftwareRenderingAndIgnoreGPUResidentContent);
-            view->setPaintBehavior(oldPaintBehavior | PaintBehaviorFlattenCompositingLayers);
-        }
+    FrameView* view = page()->mainFrame()->view();
+    PaintBehavior oldPaintBehavior = view->paintBehavior();
 
-        double paintStart = currentTime();
-        PageWidgetDelegate::paint(m_page.get(), pageOverlays(), canvas, rect, isTransparent() ? PageWidgetDelegate::Translucent : PageWidgetDelegate::Opaque);
-        double paintEnd = currentTime();
-        double pixelsPerSec = (rect.width * rect.height) / (paintEnd - paintStart);
-        blink::Platform::current()->histogramCustomCounts("Renderer4.SoftwarePaintDurationMS", (paintEnd - paintStart) * 1000, 0, 120, 30);
-        blink::Platform::current()->histogramCustomCounts("Renderer4.SoftwarePaintMegapixPerSecond", pixelsPerSec / 1000000, 10, 210, 30);
+    double paintStart = currentTime();
 
-        if (isAcceleratedCompositingActive()) {
-            ASSERT(option == ForceSoftwareRenderingAndIgnoreGPUResidentContent);
-            view->setPaintBehavior(oldPaintBehavior);
-        }
-    }
+#if OS(ANDROID)

[danakj, 2014/05/02 23:12:53]

This OS(ANDROID) stuff is a disaster.

abarth: WDYT of adding another WebWidget::paintCompositedWebViewDeprecated()
method for android that wraps a call to paint() in this setPaintBehaviour stuff,
so it's clear when this is happening and that it's wrong?

+    if (isAcceleratedCompositingActive())
+        view->setPaintBehavior(oldPaintBehavior | PaintBehaviorFlattenCompositingLayers);
+#endif
+
+    PageWidgetDelegate::paint(m_page.get(), pageOverlays(), canvas, rect, isTransparent() ? PageWidgetDelegate::Translucent : PageWidgetDelegate::Opaque);
+
+#if OS(ANDROID)
+    if (isAcceleratedCompositingActive())
+        view->setPaintBehavior(oldPaintBehavior);
+#endif
+
+    double paintEnd = currentTime();
+    double pixelsPerSec = (rect.width * rect.height) / (paintEnd - paintStart);
+    blink::Platform::current()->histogramCustomCounts("Renderer4.SoftwarePaintDurationMS", (paintEnd - paintStart) * 1000, 0, 120, 30);
+    blink::Platform::current()->histogramCustomCounts("Renderer4.SoftwarePaintMegapixPerSecond", pixelsPerSec / 1000000, 10, 210, 30);
 }
 
 bool WebViewImpl::compositeAndReadbackAsync(WebCompositeAndReadbackAsyncCallback* callback)