Windows: Improvements to off-screen rendering support (issue #518).

- Implement support for transparency. Change the backing store to use Skia instead of GDI and to keep alpha values.
- Implement support for select popups. Requires a patch to Chromium (content_popups.patch).
- Implicitly disable accelerated compositing when using off-screen rendering.
- Introduce a new CefMouseEvent structure for representing mouse event information passed to CefBrowser methods.
- Merge cef_key_event_modifiers_t into cef_event_flags_t.
- Add a new argument to CefBrowser::Invalidate telling the browser whether to invalidate the select popup or the main view.
- Add a new cefclient "transparent-painting-enabled" command-line flag to test transparent off-screen rendering.
- Add a new cefclient "Transparency" test.
- Fix the cefclient off-screen rendering rotation effect to work even when the underlying web content is not updating.
- Add unit tests for transparent painting and select popups.

git-svn-id: https://chromiumembedded.googlecode.com/svn/trunk@979 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

libcef/browser/browser_host_impl_gtk.cc

@@ -334,44 +334,51 @@ void CefBrowserHostImpl::PlatformRunFileChooser(
 void CefBrowserHostImpl::PlatformHandleExternalProtocol(const GURL& url) {
 }
 
-//static
+// static
 bool CefBrowserHostImpl::IsWindowRenderingDisabled(const CefWindowInfo& info) {
   // TODO(port): Implement this method as part of off-screen rendering support.
   return false;
 }
 
-// static
-bool CefBrowserHostImpl::PlatformTranslateKeyEvent(
-    gfx::NativeEvent& native_event, const CefKeyEvent& event) {
+bool CefBrowserHostImpl::IsTransparent() {
+  return false;
+}
+
+void CefBrowserHostImpl::PlatformTranslateKeyEvent(
+    content::NativeWebKeyboardEvent& native_event,
+    const CefKeyEvent& event) {
   // TODO(port): Implement this method as part of off-screen rendering support.
   NOTIMPLEMENTED();
-  return false;
 }
 
-// static
-bool CefBrowserHostImpl::PlatformTranslateClickEvent(
-    WebKit::WebMouseEvent& ev, 
-    int x, int y, MouseButtonType type, 
-    bool mouseUp, int clickCount) {
-  // TODO(port): Implement this method as part of off-screen rendering support. 
-  NOTIMPLEMENTED();
-  return false;
-}
-
-// static
-bool CefBrowserHostImpl::PlatformTranslateMoveEvent(
+void CefBrowserHostImpl::PlatformTranslateClickEvent(
     WebKit::WebMouseEvent& ev,
-    int x, int y, bool mouseLeave) {
+    const CefMouseEvent& mouse_event,
+    MouseButtonType type,
+    bool mouseUp, int clickCount) {
   // TODO(port): Implement this method as part of off-screen rendering support.
   NOTIMPLEMENTED();
-  return false;
 }
 
-// static
-bool CefBrowserHostImpl::PlatformTranslateWheelEvent(
-    WebKit::WebMouseWheelEvent& ev,
-    int x, int y, int deltaX, int deltaY) {
+void CefBrowserHostImpl::PlatformTranslateMoveEvent(
+    WebKit::WebMouseEvent& ev,
+    const CefMouseEvent& mouse_event,
+    bool mouseLeave) {
+  // TODO(port): Implement this method as part of off-screen rendering support.
+  NOTIMPLEMENTED();
+}
+
+void CefBrowserHostImpl::PlatformTranslateWheelEvent(
+    WebKit::WebMouseWheelEvent& ev,
+    const CefMouseEvent& mouse_event,
+    int deltaX, int deltaY) {
+  // TODO(port): Implement this method as part of off-screen rendering support.
+  NOTIMPLEMENTED();
+}
+
+void CefBrowserHostImpl::PlatformTranslateMouseEvent(
+    WebKit::WebMouseEvent& ev,
+    const CefMouseEvent& mouse_event) {
   // TODO(port): Implement this method as part of off-screen rendering support.
   NOTIMPLEMENTED();
-  return false;
 }