Route OnDragEvent through ViewAndroid tree

ui/events/android/drag_event_android.cc

Index: ui/events/android/drag_event_android.cc
diff --git a/ui/events/android/drag_event_android.cc b/ui/events/android/drag_event_android.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e5a5e30b69e9993aa42fafbd9011139d97675412
--- /dev/null
+++ b/ui/events/android/drag_event_android.cc
@@ -0,0 +1,51 @@
+// 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/events/android/drag_event_android.h"
+#include "base/android/jni_android.h"
+
+using base::android::ScopedJavaLocalRef;
+using base::android::AttachCurrentThread;
+
+namespace ui {
+
+DragEventAndroid::DragEventAndroid(
+    JNIEnv* env,
+    int action,
+    const gfx::PointF& location,
+    const gfx::PointF& screen_location,
+    const std::vector<base::string16>& mime_types,
+    jstring content)
+    : action_(action),
+      location_(location),
+      screen_location_(screen_location),
+      mime_types_(mime_types) {
+  content_.Reset(env, content);
+}
+
+DragEventAndroid::~DragEventAndroid() {}
+
+const gfx::Point DragEventAndroid::GetLocation() const {
+  return gfx::ToFlooredPoint(location_);
+}
+
+const gfx::Point DragEventAndroid::GetScreenLocation() const {
+  return gfx::ToFlooredPoint(screen_location_);
+}
+
+ScopedJavaLocalRef<jstring> DragEventAndroid::GetJavaContent() const {
+  return ScopedJavaLocalRef<jstring>(content_);
+}
+
+std::unique_ptr<DragEventAndroid> DragEventAndroid::CreateFor(
+    const gfx::PointF& new_location) const {
+  gfx::PointF new_screen_location =
+      new_location + (screen_location_f() - location_f());
+  JNIEnv* env = AttachCurrentThread();
+  return std::unique_ptr<DragEventAndroid>(
+      new DragEventAndroid(env, action_, new_location, new_screen_location,
+                           mime_types_, content_.obj()));
+}
+
+}  // namespace ui