ViewRoot class for event forwarding on Android

ui/android/view_root.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/android/view_root.h"
+
+#include "jni/ViewRoot_jni.h"
+
+namespace ui {
+
+using base::android::JavaParamRef;
+
+ViewRoot::ViewRoot(jlong window_android_ptr) {
+  WindowAndroid* window_android =
+          reinterpret_cast<WindowAndroid*>(window_android_ptr);
+  window_ = window_android;
+
+  // ViewRoot simply accepts all events and lets the hit testing
+  // start from its children.
+  SetBounds(gfx::Point(), Bounds::kMatchParent, Bounds::kMatchParent);
+}
+
+void ViewRoot::Destroy(JNIEnv* env, const JavaParamRef<jobject>& obj) {
+  delete this;
+}
+
+ViewAndroid* ViewRoot::GetViewRoot() {
+  return this;
+}
+
+WindowAndroid* ViewRoot::GetWindowAndroid() const {
+  return window_;
+}
+
+void ViewRoot::MoveToFront(ViewAndroid* child) {
+  DCHECK(child);
+  auto it = std::find(children_.begin(), children_.end(), child);
+  DCHECK(it != children_.end());
+
+  if (it != children_.begin())
+    children_.splice(children_.begin(), children_, it);
+}
+
+jboolean ViewRoot::OnTouchEvent(JNIEnv* env,
+                                const JavaParamRef<jobject>& obj,
+                                const JavaParamRef<jobject>& motion_event,
+                                jlong time_ms,
+                                jint android_action,
+                                jint pointer_count,
+                                jint history_size,
+                                jint action_index,
+                                jfloat pos_x_0,
+                                jfloat pos_y_0,
+                                jfloat pos_x_1,
+                                jfloat pos_y_1,
+                                jint pointer_id_0,
+                                jint pointer_id_1,
+                                jfloat touch_major_0,
+                                jfloat touch_major_1,
+                                jfloat touch_minor_0,
+                                jfloat touch_minor_1,
+                                jfloat orientation_0,
+                                jfloat orientation_1,
+                                jfloat tilt_0,
+                                jfloat tilt_1,
+                                jfloat raw_pos_x,
+                                jfloat raw_pos_y,
+                                jint android_tool_type_0,
+                                jint android_tool_type_1,
+                                jint android_button_state,
+                                jint android_meta_state,
+                                jboolean is_touch_handle_event) {
+  MotionEventData event(GetDipScale(),
+                        motion_event.obj(),
+                        time_ms,
+                        android_action,
+                        pointer_count,
+                        history_size,
+                        action_index,
+                        pos_x_0,
+                        pos_y_0,
+                        pos_x_1,
+                        pos_y_1,
+                        pointer_id_0,
+                        pointer_id_1,
+                        touch_major_0,
+                        touch_major_1,
+                        touch_minor_0,
+                        touch_minor_1,
+                        orientation_0,
+                        orientation_1,
+                        tilt_0,
+                        tilt_1,
+                        raw_pos_x,
+                        raw_pos_y,
+                        android_tool_type_0,
+                        android_tool_type_1,
+                        android_button_state,
+                        android_meta_state,
+                        is_touch_handle_event);
+  return OnTouchEventInternal(event);
+}
+
+// static
+jlong Init(JNIEnv* env,
+           const JavaParamRef<jobject>& obj,
+           jlong window_android_ptr) {
+  return reinterpret_cast<intptr_t>(new ViewRoot(window_android_ptr));
+}
+
+bool RegisterViewRoot(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+}  // namespace ui