Move content offset to ViewAndroid

Content offset is specific to a given web contents/render widget.
This CL moves the offset info from WindwoAndroid to ViewAndroid,
and it is used to get the correct bounds for snapshot API.

BUG=617750

Review-Url: https://codereview.chromium.org/2219823002
Cr-Commit-Position: refs/heads/master@{#442442}

content/browser/android/content_view_core_impl.cc

@@ -422,9 +422,6 @@ void ContentViewCoreImpl::UpdateFrameInfo(
   if (obj.is_null() || !GetWindowAndroid())
     return;
 
-  GetWindowAndroid()->set_content_offset(
-      gfx::Vector2dF(0.0f, top_controls_height * top_controls_shown_ratio));
-
   page_scale_ = page_scale_factor;
 
   // The CursorAnchorInfo API in Android only supports zero width selection

content/browser/renderer_host/render_widget_host_impl.cc

@@ -91,6 +91,10 @@
 #include "ui/gfx/skbitmap_operations.h"
 #include "ui/snapshot/snapshot.h"
 
+#if defined(OS_ANDROID)
+#include "ui/android/view_android.h"
+#endif
+
 #if defined(OS_MACOSX)
 #include "device/power_save_blocker/power_save_blocker.h"
 #include "ui/accelerated_widget_mac/window_resize_helper_mac.h"
@@ -2353,8 +2357,14 @@ void RenderWidgetHostImpl::DidReceiveRendererFrame() {
 void RenderWidgetHostImpl::WindowSnapshotReachedScreen(int snapshot_id) {
   DCHECK(base::MessageLoopForUI::IsCurrent());
 
-  gfx::Rect view_bounds = GetView()->GetViewBounds();
-  gfx::Rect snapshot_bounds(view_bounds.size());
+#if defined(OS_ANDROID)
+  // On Android, call sites should pass in the bounds with correct offset
+  // to capture the intended content area.
+  gfx::Rect snapshot_bounds(GetView()->GetViewBounds());
+  snapshot_bounds.Offset(0, GetView()->GetNativeView()->content_offset().y());
+#else
+  gfx::Rect snapshot_bounds(GetView()->GetViewBounds().size());
+#endif
 
   std::vector<unsigned char> png;
   if (ui::GrabViewSnapshot(

content/browser/renderer_host/render_widget_host_view_android.cc

@@ -1357,6 +1357,10 @@ void RenderWidgetHostViewAndroid::OnFrameMetadataUpdated(
   UpdateBackgroundColor(is_transparent ? SK_ColorTRANSPARENT
                                        : frame_metadata.root_background_color);
 
+  view_.set_content_offset(gfx::Vector2dF(0.0f,
+      frame_metadata.top_controls_height *
+          frame_metadata.top_controls_shown_ratio));
+
   // All offsets and sizes are in CSS pixels.
   content_view_core_->UpdateFrameInfo(
       frame_metadata.root_scroll_offset,

ui/android/view_android.cc

@@ -140,10 +140,7 @@ void ViewAndroid::SetAnchorRect(const JavaRef<jobject>& anchor,
       ->GetDisplayNearestWindow(this)
       .device_scale_factor();
   int left_margin = std::round(bounds.x() * scale);
-  // TODO(jinsukkim): Move content_offset() to ViewAndroid, since it's
-  //                  specific to a given web contents/render widget.
-  int top_margin = std::round(
-      (GetWindowAndroid()->content_offset().y() + bounds.y()) * scale);
+  int top_margin = std::round((content_offset().y() + bounds.y()) * scale);
   JNIEnv* env = base::android::AttachCurrentThread();
   Java_ViewAndroidDelegate_setViewPosition(
       env, delegate, anchor, bounds.x(), bounds.y(), bounds.width(),

ui/android/view_android.h

@@ -60,6 +60,16 @@ class UI_ANDROID_EXPORT ViewAndroid {
   ViewAndroid();
   virtual ~ViewAndroid();
 
+  // The content offset is in CSS pixels, and is used to translate
+  // snapshots to the correct part of the view.
+  void set_content_offset(const gfx::Vector2dF& content_offset) {
+    content_offset_ = content_offset;
+  }
+
+  gfx::Vector2dF content_offset() const {
+    return content_offset_;
+  }
+
   // Returns the window at the root of this hierarchy, or |null|
   // if disconnected.
   virtual WindowAndroid* GetWindowAndroid() const;
@@ -126,6 +136,7 @@ class UI_ANDROID_EXPORT ViewAndroid {
 
   int physical_width_pix_;
   int physical_height_pix_;
+  gfx::Vector2dF content_offset_;  // in CSS pixel
 
   DISALLOW_COPY_AND_ASSIGN(ViewAndroid);
 };

ui/android/window_android.h

@@ -46,16 +46,6 @@ class UI_ANDROID_EXPORT WindowAndroid : public ViewAndroid {
 
   static bool RegisterWindowAndroid(JNIEnv* env);
 
-  // The content offset in CSS pixels. It is used together with device scale
-  // factor to translate snapshots to the correct part of the window.
-  void set_content_offset(const gfx::Vector2dF& content_offset) {
-    content_offset_ = content_offset;
-  }
-
-  gfx::Vector2dF content_offset() const {
-    return content_offset_;
-  }
-
   // Compositor callback relay.
   void OnCompositingDidCommit();
 
@@ -113,7 +103,6 @@ class UI_ANDROID_EXPORT WindowAndroid : public ViewAndroid {
 
   base::android::ScopedJavaGlobalRef<jobject> java_window_;
   const int display_id_;
-  gfx::Vector2dF content_offset_;
   WindowAndroidCompositor* compositor_;
 
   base::ObserverList<WindowAndroidObserver> observer_list_;

ui/snapshot/snapshot_android.cc

@@ -21,6 +21,8 @@
 
 namespace ui {
 
+// Sync versions are not supported in Android.  Callers should fall back
+// to the async version.
 bool GrabViewSnapshot(gfx::NativeView view,
                       std::vector<unsigned char>* png_representation,
                       const gfx::Rect& snapshot_bounds) {
@@ -31,7 +33,6 @@ bool GrabViewSnapshot(gfx::NativeView view,
 bool GrabWindowSnapshot(gfx::NativeWindow window,
                         std::vector<unsigned char>* png_representation,
                         const gfx::Rect& snapshot_bounds) {
-  // Not supported in Android.  Callers should fall back to the async version.
   return false;
 }
 
@@ -44,20 +45,8 @@ static void MakeAsyncCopyRequest(
 
   const display::Display& display =
       display::Screen::GetScreen()->GetDisplayNearestWindow(window);
-  float device_scale_factor = display.device_scale_factor();
-  gfx::Rect source_rect_in_pixel =
-      gfx::ScaleToEnclosingRect(source_rect, device_scale_factor);
-
-  // Account for the toolbar offset.
-  gfx::Vector2dF offset_in_pixel =
-      gfx::ScaleVector2d(window->content_offset(), device_scale_factor);
-  gfx::Rect adjusted_source_rect(
-      gfx::ToRoundedPoint(
-          gfx::PointF(source_rect_in_pixel.x() + offset_in_pixel.x(),
-                      source_rect_in_pixel.y() + offset_in_pixel.y())),
-      source_rect_in_pixel.size());
-
-  request->set_area(adjusted_source_rect);
+  float scale = display.device_scale_factor();
+  request->set_area(gfx::ScaleToEnclosingRect(source_rect, scale));
   window->GetCompositor()->RequestCopyOfOutputOnRootLayer(std::move(request));
 }
 
@@ -92,8 +81,11 @@ void GrabViewSnapshotAsync(
     const gfx::Rect& source_rect,
     scoped_refptr<base::TaskRunner> background_task_runner,
     const GrabWindowSnapshotAsyncPNGCallback& callback) {
-  GrabWindowSnapshotAsync(
-      view->GetWindowAndroid(), source_rect, background_task_runner, callback);
+  MakeAsyncCopyRequest(view->GetWindowAndroid(),
+                       source_rect,
+                       base::Bind(&SnapshotAsync::EncodeCopyOutputResult,
+                                  callback,
+                                  background_task_runner));
 }
 
 }  // namespace ui