Make WebView work for external displays (over Presentations).

ui/gfx/android/device_display_info.h

 // Copyright (c) 2012 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.
 
 #ifndef UI_GFX_ANDROID_DEVICE_DISPLAY_INFO_H_
 #define UI_GFX_ANDROID_DEVICE_DISPLAY_INFO_H_
 
 #include <jni.h>
 #include <string>
 
+#include "base/android/jni_android.h"
 #include "base/basictypes.h"
 #include "ui/gfx/gfx_export.h"
 
 namespace gfx {
 
 // Facilitates access to device information typically only
 // available using the Android SDK, including Display properties.
 class GFX_EXPORT DeviceDisplayInfo {
  public:
   DeviceDisplayInfo();
+  explicit DeviceDisplayInfo(
+      base::android::ScopedJavaLocalRef<jobject> context);
   ~DeviceDisplayInfo();
 
+  void FetchDisplayInfoFromJava(JNIEnv* env);
+
   // Returns display height in physical pixels.
   int GetDisplayHeight();
 
   // Returns display width in physical pixels.
   int GetDisplayWidth();
 
   // Returns real display height in physical pixels.
   // This version does not subtract window decorations etc.
   // WARNING: This is only supported on JB-MR1 (sdk >= 17). Either
   //          check the SDK-level, or check for '0' being returned.
@@ skipping 16 matching lines @@
   double GetDIPScale();
 
   // Smallest possible screen size in density-independent pixels.
   int GetSmallestDIPWidth();
 
   // Returns the display rotation angle from its natural orientation. Expected
   // values are one of { 0, 90, 180, 270 }.
   // See DeviceDispayInfo.java for more information.
   int GetRotationDegrees();
 
+  // Registers methods with JNI and returns true if succeeded.
+  static bool RegisterDeviceDisplayInfo(JNIEnv* env);
+
+ private:
+  void UpdateDisplayInfo(jint display_height,
+                         jint display_width,
+                         jint physical_display_height,
+                         jint physical_display_width,
+                         jint bits_per_pixel,
+                         jint bits_per_component,
+                         jdouble dip_scale,
+                         jint smallest_dip_width,
+                         jint rotation_degrees);
+
+  base::android::ScopedJavaGlobalRef<jobject> j_device_info_;
+
+  int display_height_;
+  int display_width_;
+  int physical_display_height_;
+  int physical_display_width_;
+  int bits_per_pixel_;
+  int bits_per_component_;
+  double dip_scale_;
+  int smallest_dip_width_;
+  int rotation_degrees_;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(DeviceDisplayInfo);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_ANDROID_DEVICE_DISPLAY_INFO_H_