Sets a transparent background for out-of-process subframes.

third_party/WebKit/Source/web/WebFrameWidgetImpl.cpp

 /*
  * Copyright (C) 2014 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 45 matching lines @@
 #include "web/WebRemoteFrameImpl.h"
 #include "web/WebViewFrameWidget.h"
 
 namespace blink {
 
 // WebFrameWidget ----------------------------------------------------------------
 
 WebFrameWidget* WebFrameWidget::create(WebWidgetClient* client, WebLocalFrame* localRoot)
 {
     // Pass the WebFrameWidget's self-reference to the caller.
-    return WebFrameWidgetImpl::create(client, localRoot);
+    WebFrameWidgetImpl* widget = WebFrameWidgetImpl::create(client, localRoot);
+    if (localRoot->parent())

[dcheng, 2016/02/11 22:40:26]

Do you think it'd make sense to have this in the ctor? That way, if someone
accidentally calls WebFrameWidgetImpl::create(), they still get the right
default.

[lfg, 2016/02/11 23:48:02]

Done.

+        widget->setIsTransparent(true);
+    return widget;
 }
 
 WebFrameWidget* WebFrameWidget::create(WebWidgetClient* client, WebView* webView, WebLocalFrame* mainFrame)
 {
     return new WebViewFrameWidget(client, toWebViewImpl(*webView), toWebLocalFrameImpl(*mainFrame));
 }
 
 WebFrameWidgetImpl* WebFrameWidgetImpl::create(WebWidgetClient* client, WebLocalFrame* localRoot)
 {
     // Pass the WebFrameWidgetImpl's self-reference to the caller.
@@ skipping 14 matching lines @@
 WebFrameWidgetImpl::WebFrameWidgetImpl(WebWidgetClient* client, WebLocalFrame* localRoot)
     : m_client(client)
     , m_localRoot(toWebLocalFrameImpl(localRoot))
     , m_layerTreeView(nullptr)
     , m_rootLayer(nullptr)
     , m_rootGraphicsLayer(nullptr)
     , m_isAcceleratedCompositingActive(false)
     , m_layerTreeViewClosed(false)
     , m_suppressNextKeypressEvent(false)
     , m_ignoreInputEvents(false)
+    , m_isTransparent(false)
 #if ENABLE(OILPAN)
     , m_selfKeepAlive(this)
 #endif
 {
     ASSERT(m_localRoot->frame()->isLocalRoot());
     initializeLayerTreeView();
     m_localRoot->setFrameWidget(this);
     allInstances().add(this);
 }
 
@@ skipping 160 matching lines @@
 
     // FIXME: We need access to page scale information from the WebView.
     m_layerTreeView->setPageScaleFactorAndLimits(1, 1, 1);
 }
 
 void WebFrameWidgetImpl::updateLayerTreeBackgroundColor()
 {
     if (!m_layerTreeView)
         return;
 
-    m_layerTreeView->setBackgroundColor(alphaChannel(view()->backgroundColorOverride()) ? view()->backgroundColorOverride() : view()->backgroundColor());
+    m_layerTreeView->setBackgroundColor(backgroundColor());
 }
 
 void WebFrameWidgetImpl::updateLayerTreeDeviceScaleFactor()
 {
     ASSERT(page());
     ASSERT(m_layerTreeView);
 
     float deviceScaleFactor = page()->deviceScaleFactor();
     m_layerTreeView->setDeviceScaleFactor(deviceScaleFactor);
 }
 
+void WebFrameWidgetImpl::setIsTransparent(bool isTransparent)
+{
+    m_isTransparent = isTransparent;
+

[dcheng, 2016/02/11 22:40:26]

The WebView version also marks the FrameViews as transparent: do we need
anything like that?

[lfg, 2016/02/11 23:48:02]

I believe this is correct. isTransparent() on FrameView only controls painting
the background if it's the main frame (iframes are transparent by default), and
controls things that should be treated differently when the main frame's
background is transparent. In this case, the main frame is not transparent, we
just want to drop the background layer in the local root's widget.

However, we may want to set the frameviews as transparent when the WebViewImpl
in the main frame is set as transparent, but looking at usages of
FrameView::isTransparent(), I don't think we are breaking anything by not
replicating this parameter.

[dcheng, 2016/02/12 22:46:23]

Hm... I guess I am thinking that it would make it easier to merge widget
portions of WebView into WebFrameWidget into the future. But I guess at that
point, we'll have to manually diff and reconcile any behavior differences...
maybe a TODO could be useful though.

+    if (m_layerTreeView)
+        m_layerTreeView->setHasTransparentBackground(isTransparent);
+}
+
 bool WebFrameWidgetImpl::isTransparent() const
 {
-    // FIXME: This might need to proxy to the WebView's isTransparent().
-    return false;
+    return m_isTransparent;
 }
 
 void WebFrameWidgetImpl::layoutAndPaintAsync(WebLayoutAndPaintAsyncCallback* callback)
 {
     m_layerTreeView->layoutAndPaintAsync(callback);
 }
 
 void WebFrameWidgetImpl::compositeAndReadbackAsync(WebCompositeAndReadbackAsyncCallback* callback)
 {
     m_layerTreeView->compositeAndReadbackAsync(callback);
@@ skipping 67 matching lines @@
 {
     page()->setIsCursorVisible(isVisible);
 }
 
 bool WebFrameWidgetImpl::hasTouchEventHandlersAt(const WebPoint& point)
 {
     // FIXME: Implement this. Note that the point must be divided by pageScaleFactor.
     return true;
 }
 
+void WebFrameWidgetImpl::setBaseBackgroundColor(WebColor color)
+{
+    if (m_baseBackgroundColor == color)
+        return;
+
+    m_baseBackgroundColor = color;
+
+    m_localRoot->frameView()->setBaseBackgroundColor(color);
+
+    updateAllLifecyclePhases();
+}
+
 void WebFrameWidgetImpl::scheduleAnimation()
 {
     if (m_layerTreeView) {
         m_layerTreeView->setNeedsBeginFrame();
         return;
     }
     if (m_client)
         m_client->scheduleAnimation();
 }
 
@@ skipping 82 matching lines @@
 WebTextInputType WebFrameWidgetImpl::textInputType()
 {
     return view()->textInputType();
 }
 
 WebColor WebFrameWidgetImpl::backgroundColor() const
 {
     if (isTransparent())
         return Color::transparent;
     if (!m_localRoot->frameView())
-        return view()->backgroundColor();
+        return m_baseBackgroundColor;
     FrameView* view = m_localRoot->frameView();
     return view->documentBackgroundColor().rgb();
 }
 
 bool WebFrameWidgetImpl::selectionBounds(WebRect& anchor, WebRect& focus) const
 {
     const Frame* frame = focusedCoreFrame();
     if (!frame || !frame->isLocalFrame())
         return false;
 
@@ skipping 585 matching lines @@
 
 HitTestResult WebFrameWidgetImpl::hitTestResultForRootFramePos(const IntPoint& posInRootFrame)
 {
     IntPoint docPoint(m_localRoot->frame()->view()->rootFrameToContents(posInRootFrame));
     HitTestResult result = m_localRoot->frame()->eventHandler().hitTestResultAtPoint(docPoint, HitTestRequest::ReadOnly | HitTestRequest::Active);
     result.setToShadowHostIfInUserAgentShadowRoot();
     return result;
 }
 
 } // namespace blink