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/backing_store_osr.cc

@@ -4,22 +4,79 @@
 
 #include "libcef/browser/backing_store_osr.h"
 
+#include "content/public/browser/render_process_host.h"
 #include "ui/gfx/rect.h"
+#include "ui/surface/transport_dib.h"
 
 BackingStoreOSR::BackingStoreOSR(content::RenderWidgetHost* widget,
                                  const gfx::Size& size)
-    : content::BackingStore(widget, size) {
-  bitmap_.Allocate(size.width(), size.height(), true);
+    : content::BackingStore(widget, size),
+      device_(SkBitmap::kARGB_8888_Config, size.width(), size.height(), true),
+      canvas_(&device_) {
+  canvas_.drawColor(SK_ColorWHITE);
+}
+
+void BackingStoreOSR::PaintToBackingStore(
+    content::RenderProcessHost* process,
+    TransportDIB::Id bitmap,
+    const gfx::Rect& bitmap_rect,
+    const std::vector<gfx::Rect>& copy_rects,
+    float scale_factor,
+    const base::Closure& completion_callback,
+    bool* scheduled_completion_callback) {
+  *scheduled_completion_callback = false;
+  TransportDIB* dib = process->GetTransportDIB(bitmap);
+  if (!dib)
+    return;
+
+  SkBitmap src_bitmap;
+  src_bitmap.setConfig(SkBitmap::kARGB_8888_Config,
+                       bitmap_rect.width(),
+                       bitmap_rect.height());
+  src_bitmap.setPixels(dib->memory());
+
+  SkPaint copy_paint;
+  copy_paint.setXfermodeMode(SkXfermode::kSrc_Mode);
+
+  for (size_t i = 0; i < copy_rects.size(); i++) {
+    SkIRect src_rect = SkIRect::MakeXYWH(copy_rects[i].x() - bitmap_rect.x(),
+                                         copy_rects[i].y() - bitmap_rect.y(),
+                                         copy_rects[i].width(),
+                                         copy_rects[i].height());
+    SkRect paint_rect = SkRect::MakeXYWH(copy_rects[i].x(),
+                                         copy_rects[i].y(),
+                                         copy_rects[i].width(),
+                                         copy_rects[i].height());
+    canvas_.drawBitmapRect(src_bitmap, &src_rect, paint_rect, &copy_paint);
+  }
+  src_bitmap.setPixels(0);
+}
+
+bool BackingStoreOSR::CopyFromBackingStore(const gfx::Rect& rect,
+                                           skia::PlatformBitmap* output) {
+  if (!output->Allocate(rect.width(), rect.height(), true))
+    return false;
+
+  SkPaint copy_paint;
+  copy_paint.setXfermodeMode(SkXfermode::kSrc_Mode);
+
+  SkCanvas canvas(output->GetBitmap());
+  canvas.drawColor(SK_ColorWHITE);
+  canvas.drawBitmap(device_.accessBitmap(false), 0, 0, &copy_paint);
+  return true;
 }
 
 void BackingStoreOSR::ScrollBackingStore(const gfx::Vector2d& delta,
                                          const gfx::Rect& clip_rect,
                                          const gfx::Size& view_size) {
-  SkIRect subset_rect = SkIRect::MakeXYWH(clip_rect.x(), clip_rect.y(),
-      clip_rect.width(), clip_rect.height());
-  bitmap_.GetBitmap().scrollRect(&subset_rect, delta.x(), delta.y());
+  SkIRect subset_rect = SkIRect::MakeXYWH(clip_rect.x(),
+                                          clip_rect.y(),
+                                          clip_rect.width(),
+                                          clip_rect.height());
+  device_.accessBitmap(true).scrollRect(&subset_rect, delta.x(), delta.y());
 }
 
 const void* BackingStoreOSR::getPixels() const {
-  return const_cast<BackingStoreOSR*>(this)->bitmap_.GetBitmap().getPixels();
+  return const_cast<BackingStoreOSR*>(this)->device_.
+      accessBitmap(false).getPixels();
 }