Introduce ViewRoot to forward input/view events to native

ui/android/view_android.cc

Index: ui/android/view_android.cc
diff --git a/ui/android/view_android.cc b/ui/android/view_android.cc
index 664758cd5304088709f1cd99bdb655bae764aadf..254302320d61ce38b8a8c1f2de9f589e458b9579 100644
--- a/ui/android/view_android.cc
+++ b/ui/android/view_android.cc
@@ -9,12 +9,14 @@
 #include "base/android/jni_android.h"
 #include "cc/layers/layer.h"
 #include "jni/ViewAndroidDelegate_jni.h"
+#include "ui/android/view_client.h"
 #include "ui/android/window_android.h"
 #include "ui/display/display.h"
 #include "ui/display/screen.h"
 
 namespace ui {
 
+using base::android::JavaParamRef;
 using base::android::JavaRef;
 using base::android::ScopedJavaLocalRef;
 
@@ -68,12 +70,9 @@ ViewAndroid::ScopedAnchorView::view() const {
   return view_.get(env);
 }
 
-ViewAndroid::ViewAndroid(const JavaRef<jobject>& delegate)
-    : parent_(nullptr)
-    , delegate_(base::android::AttachCurrentThread(),
-                delegate.obj()) {}
-
-ViewAndroid::ViewAndroid() : parent_(nullptr) {}
+ViewAndroid::ViewAndroid(ViewClient* client) : parent_(nullptr),
+                                               client_(client) {}
+ViewAndroid::ViewAndroid() : ViewAndroid(nullptr) {}
 
 ViewAndroid::~ViewAndroid() {
   RemoveFromParent();
@@ -86,6 +85,8 @@ ViewAndroid::~ViewAndroid() {
 }
 
 void ViewAndroid::SetDelegate(const JavaRef<jobject>& delegate) {
+  // A ViewAndroid may have its own delegate or otherwise will
+  // use the next available parent's delegate.
   JNIEnv* env = base::android::AttachCurrentThread();
   delegate_ = JavaObjectWeakGlobalRef(env, delegate);
 }
@@ -179,4 +180,53 @@ bool ViewAndroid::StartDragAndDrop(const JavaRef<jstring>& jtext,
                                                    jimage);
 }
 
+int ViewAndroid::GetPhysicalBackingSizeWidthPix() {
+  if (!parent_ || parent_ == GetWindowAndroid())

[boliu, 2016/12/06 00:34:14]

should just return own size, not recurse

ie we should pay the cost to update the whole tree in SetPhysicalBackingSize, so
that the getter is free

[Jinsuk Kim, 2016/12/06 07:35:07]

Done.

+    return physical_width_pix_;
+  else
+    return parent_->GetPhysicalBackingSizeWidthPix();
+}
+
+int ViewAndroid::GetPhysicalBackingSizeHeightPix() {
+  if (!parent_ || parent_ == GetWindowAndroid())
+    return physical_height_pix_;
+  else
+    return parent_->GetPhysicalBackingSizeHeightPix();
+}
+
+gfx::Size ViewAndroid::GetPhysicalBackingSize() {
+  return gfx::Size(GetPhysicalBackingSizeWidthPix(),
+                   GetPhysicalBackingSizeHeightPix());
+}
+
+void ViewAndroid::SetPhysicalBackingSize(int width, int height) {
+  if (!parent_ || parent_ == GetWindowAndroid()) {
+    physical_width_pix_ = width;
+    physical_height_pix_ = height;
+  } else {
+    return parent_->SetPhysicalBackingSize(width, height);

[boliu, 2016/12/06 00:34:14]

recursion in the wrong direction.. this value should be propagated *down*, not
up?

oh actually, looking at OnPhysicalBackingSizeChanged below, this should not
recurse at all?

[Jinsuk Kim, 2016/12/06 07:35:07]

Done.

+  }
+}
+
+void ViewAndroid::UpdateLayerBounds() {
+  layer_->SetBounds(GetPhysicalBackingSize());

[boliu, 2016/12/06 00:34:14]

just do this inside SetPhyiscalBackingSize, then client don't ever need to worry
about UpdateLayerBounds

[Jinsuk Kim, 2016/12/06 07:35:07]

Done.

+}
+
+bool ViewAndroid::OnPhysicalBackingSizeChanged(int width, int height) {
+  if (width == GetPhysicalBackingSizeWidthPix()
+       && height == GetPhysicalBackingSizeHeightPix())
+    return true;
+
+  if (client_ && client_->OnPhysicalBackingSizeChanged(width, height)) {
+    SetPhysicalBackingSize(width, height);
+    UpdateLayerBounds();
+    return true;
+  }
+  for (auto it = children_.begin(); it != children_.end(); ++it) {
+    if ((*it)->OnPhysicalBackingSizeChanged(width, height))
+      return true;
+  }
+  return false;
+}
+
 }  // namespace ui