Add ability to copy unscaled output pixels.

BUG=427418

Review URL: https://codereview.chromium.org/802343002

Cr-Commit-Position: refs/heads/master@{#309542}

content/browser/compositor/delegated_frame_host.cc

@@ -180,7 +180,8 @@ void DelegatedFrameHost::CopyFromCompositingSurface(
           output_size,
           color_type,
           callback));
-  request->set_area(src_subrect);
+  if (!src_subrect.IsEmpty())
+    request->set_area(src_subrect);
   client_->RequestCopyOfOutput(request.Pass());
 }
 
@@ -569,9 +570,15 @@ void DelegatedFrameHost::CopyFromCompositingSurfaceHasResult(
     return;
   }
 
+  gfx::Size output_size_in_pixel;
+  if (dst_size_in_pixel.IsEmpty())
+    output_size_in_pixel = result->size();
+  else
+    output_size_in_pixel = dst_size_in_pixel;
+
   if (result->HasTexture()) {
     // GPU-accelerated path
-    PrepareTextureCopyOutputResult(dst_size_in_pixel, color_type,
+    PrepareTextureCopyOutputResult(output_size_in_pixel, color_type,
                                    callback,
                                    result.Pass());
     return;
@@ -579,7 +586,7 @@ void DelegatedFrameHost::CopyFromCompositingSurfaceHasResult(
 
   DCHECK(result->HasBitmap());
   // Software path
-  PrepareBitmapCopyOutputResult(dst_size_in_pixel, color_type, callback,
+  PrepareBitmapCopyOutputResult(output_size_in_pixel, color_type, callback,
                                 result.Pass());
 }
 

content/browser/renderer_host/render_widget_host_view_android.cc

@@ -971,7 +971,8 @@ void RenderWidgetHostViewAndroid::CopyFromCompositingSurface(
                  start_time,
                  readback_layer,
                  callback));
-  request->set_area(src_subrect_in_pixel);
+  if (!src_subrect_in_pixel.IsEmpty())
+    request->set_area(src_subrect_in_pixel);
   readback_layer->RequestCopyOfOutput(request.Pass());
 }
 
@@ -1285,6 +1286,20 @@ void RenderWidgetHostViewAndroid::SynchronousCopyContents(
     const gfx::Size& dst_size_in_pixel,
     ReadbackRequestCallback& callback,
     const SkColorType color_type) {
+  gfx::Size input_size_in_pixel;
+  if (src_subrect_in_pixel.IsEmpty())
+    input_size_in_pixel = content_size_in_layer_;
+  else
+    input_size_in_pixel = src_subrect_in_pixel.size();
+
+  gfx::Size output_size_in_pixel;
+  if (dst_size_in_pixel.IsEmpty())
+    output_size_in_pixel = input_size_in_pixel;
+  else
+    output_size_in_pixel = dst_size_in_pixel;
+  int output_width = output_size_in_pixel.width();
+  int output_height = output_size_in_pixel.height();
+
   SynchronousCompositor* compositor =
       SynchronousCompositorImpl::FromID(host_->GetProcess()->GetID(),
                                         host_->GetRoutingID());
@@ -1294,14 +1309,14 @@ void RenderWidgetHostViewAndroid::SynchronousCopyContents(
   }
 
   SkBitmap bitmap;
-  bitmap.allocPixels(SkImageInfo::Make(dst_size_in_pixel.width(),
-                                       dst_size_in_pixel.height(),
+  bitmap.allocPixels(SkImageInfo::Make(output_width,
+                                       output_height,
                                        color_type,
                                        kPremul_SkAlphaType));
   SkCanvas canvas(bitmap);
   canvas.scale(
-      (float)dst_size_in_pixel.width() / (float)src_subrect_in_pixel.width(),
-      (float)dst_size_in_pixel.height() / (float)src_subrect_in_pixel.height());
+      (float)output_width / (float)input_size_in_pixel.width(),
+      (float)output_height / (float)input_size_in_pixel.height());
   compositor->DemandDrawSw(&canvas);
   callback.Run(bitmap, READBACK_SUCCESS);
 }
@@ -1805,9 +1820,15 @@ void RenderWidgetHostViewAndroid::PrepareTextureCopyOutputResult(
   if (!result->HasTexture() || result->IsEmpty() || result->size().IsEmpty())
     return;
 
+  gfx::Size output_size_in_pixel;
+  if (dst_size_in_pixel.IsEmpty())
+    output_size_in_pixel = result->size();
+  else
+    output_size_in_pixel = dst_size_in_pixel;
+
   scoped_ptr<SkBitmap> bitmap(new SkBitmap);
-  if (!bitmap->tryAllocPixels(SkImageInfo::Make(dst_size_in_pixel.width(),
-                                                dst_size_in_pixel.height(),
+  if (!bitmap->tryAllocPixels(SkImageInfo::Make(output_size_in_pixel.width(),
+                                                output_size_in_pixel.height(),
                                                 color_type,
                                                 kOpaque_SkAlphaType))) {
     return;
@@ -1835,7 +1856,7 @@ void RenderWidgetHostViewAndroid::PrepareTextureCopyOutputResult(
       texture_mailbox.sync_point(),
       result->size(),
       gfx::Rect(result->size()),
-      dst_size_in_pixel,
+      output_size_in_pixel,
       pixels,
       color_type,
       base::Bind(&CopyFromCompositingSurfaceFinished,

content/browser/renderer_host/render_widget_host_view_base.h

@@ -256,10 +256,12 @@ class CONTENT_EXPORT RenderWidgetHostViewBase : public RenderWidgetHostView,
   // Copies the contents of the compositing surface, providing a new SkBitmap
   // result via an asynchronously-run |callback|. |src_subrect| is specified in
   // layer space coordinates for the current platform (e.g., DIP for Aura/Mac,
-  // physical for Android), and is the region to be copied from this view. The
-  // copy is then scaled to a SkBitmap of size |dst_size|. |callback| is run
-  // with true on success, false otherwise. A smaller region than |src_subrect|
-  // may be copied if the underlying surface is smaller than |src_subrect|.
+  // physical for Android), and is the region to be copied from this view. When
+  // |src_subrect| is empty then the whole surface will be copied. The copy is
+  // then scaled to a SkBitmap of size |dst_size|. If |dst_size| is empty then
+  // output will be unscaled. |callback| is run with true on success,
+  // false otherwise. A smaller region than |src_subrect| may be copied
+  // if the underlying surface is smaller than |src_subrect|.
   virtual void CopyFromCompositingSurface(const gfx::Rect& src_subrect,
                                           const gfx::Size& dst_size,
                                           ReadbackRequestCallback& callback,