[Android] Making the touch handles aware of DIP changes

Instead of caching the DIP scale at creation, query the scale from the
view.

Bug: 851634
Change-Id: Iaacec8f649fcb0da6aa01ec0859b29f8cf1281b3
Reviewed-on: https://chromium-review.googlesource.com/1099045Reviewed-by: Pedro Amaral <amaralp@chromium.org>
Commit-Queue: Aldo Culquicondor <acondor@chromium.org>
Cr-Commit-Position: refs/heads/master@{#566978}

content/browser/android/selection/composited_touch_handle_drawable.cc

@@ -10,6 +10,7 @@
 #include "cc/layers/ui_resource_layer.h"
 #include "content/public/browser/android/compositor.h"
 #include "ui/android/handle_view_resources.h"
+#include "ui/android/view_android.h"
 
 using base::android::JavaRef;
 
@@ -22,17 +23,16 @@ base::LazyInstance<ui::HandleViewResources>::Leaky g_selection_resources;
 }  // namespace
 
 CompositedTouchHandleDrawable::CompositedTouchHandleDrawable(
-    cc::Layer* root_layer,
-    float dpi_scale,
+    gfx::NativeView view,
     const JavaRef<jobject>& context)
-    : dpi_scale_(dpi_scale),
+    : view_(view),
       orientation_(ui::TouchHandleOrientation::UNDEFINED),
       layer_(cc::UIResourceLayer::Create()) {
   g_selection_resources.Get().LoadIfNecessary(context);
   drawable_horizontal_padding_ratio_ =
       g_selection_resources.Get().GetDrawableHorizontalPaddingRatio();
-  DCHECK(root_layer);
-  root_layer->AddChild(layer_.get());
+  DCHECK(view->GetLayer());
+  view->GetLayer()->AddChild(layer_.get());
 }
 
 CompositedTouchHandleDrawable::~CompositedTouchHandleDrawable() {
@@ -78,7 +78,7 @@ void CompositedTouchHandleDrawable::SetOrientation(
 }
 
 void CompositedTouchHandleDrawable::SetOrigin(const gfx::PointF& origin) {
-  origin_position_ = gfx::ScalePoint(origin, dpi_scale_);
+  origin_position_ = origin;
   UpdateLayerPosition();
 }
 
@@ -91,11 +91,10 @@ void CompositedTouchHandleDrawable::SetAlpha(float alpha) {
 }
 
 gfx::RectF CompositedTouchHandleDrawable::GetVisibleBounds() const {
-  return gfx::ScaleRect(gfx::RectF(layer_->position().x(),
-                                   layer_->position().y(),
-                                   layer_->bounds().width(),
-                                   layer_->bounds().height()),
-                        1.f / dpi_scale_);
+  return gfx::ScaleRect(
+      gfx::RectF(layer_->position().x(), layer_->position().y(),
+                 layer_->bounds().width(), layer_->bounds().height()),
+      1.f / view_->GetDipScale());
 }
 
 float CompositedTouchHandleDrawable::GetDrawableHorizontalPaddingRatio() const {
@@ -107,7 +106,7 @@ void CompositedTouchHandleDrawable::DetachLayer() {
 }
 
 void CompositedTouchHandleDrawable::UpdateLayerPosition() {
-  layer_->SetPosition(origin_position_);
+  layer_->SetPosition(gfx::ScalePoint(origin_position_, view_->GetDipScale()));
 }
 
 }  // namespace content

content/browser/android/selection/composited_touch_handle_drawable.h

@@ -8,10 +8,10 @@
 #include "base/android/scoped_java_ref.h"
 #include "base/macros.h"
 #include "base/memory/scoped_refptr.h"
+#include "ui/gfx/native_widget_types.h"
 #include "ui/touch_selection/touch_handle.h"
 
 namespace cc {
-class Layer;
 class UIResourceLayer;
 }  // namespace cc
 
@@ -20,8 +20,7 @@ namespace content {
 // Touch handle drawable implementation backed by a cc layer.
 class CompositedTouchHandleDrawable : public ui::TouchHandleDrawable {
  public:
-  CompositedTouchHandleDrawable(cc::Layer* root_layer,
-                                float dpi_scale,
+  CompositedTouchHandleDrawable(gfx::NativeView view,
                                 const base::android::JavaRef<jobject>& context);
   ~CompositedTouchHandleDrawable() override;
 
@@ -39,7 +38,7 @@ class CompositedTouchHandleDrawable : public ui::TouchHandleDrawable {
   void DetachLayer();
   void UpdateLayerPosition();
 
-  const float dpi_scale_;
+  gfx::NativeView view_;
   float drawable_horizontal_padding_ratio_;
   ui::TouchHandleOrientation orientation_;
   gfx::PointF origin_position_;

content/browser/android/selection/selection_popup_controller.cc

@@ -74,8 +74,7 @@ SelectionPopupController::CreateTouchHandleDrawable() {
   // the java side in CompositedTouchHandleDrawable.
   auto* view = web_contents()->GetNativeView();
   return std::unique_ptr<ui::TouchHandleDrawable>(
-      new CompositedTouchHandleDrawable(view->GetLayer(), view->GetDipScale(),
-                                        activityContext));
+      new CompositedTouchHandleDrawable(view, activityContext));
 }
 
 void SelectionPopupController::MoveRangeSelectionExtent(