Move HiDPI-related Pepper interfaces to stable

ppapi/cpp/graphics_2d.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 PPAPI_CPP_GRAPHICS_2D_H_
 #define PPAPI_CPP_GRAPHICS_2D_H_
 
 #include "ppapi/c/pp_stdint.h"
 #include "ppapi/cpp/resource.h"
 #include "ppapi/cpp/size.h"
@@ skipping 242 matching lines @@
   /// not issued its callback yet.  In the failure case, nothing will be
   /// updated and no callback will be scheduled.
 
   // TODO(darin): We should ensure that the completion callback always runs, so
   // that it is easier for consumers to manage memory referenced by a callback.
 
   // TODO(): Add back in the synchronous mode description once we have support
   // for it.
   int32_t Flush(const CompletionCallback& cc);
 
+  /// SetScale() sets the scale factor that will be applied when painting the
+  /// graphics context onto the output device. Typically, if rendering at device
+  /// resolution is desired, the context would be created with the width and
+  /// height scaled up by the view's GetDeviceScale and SetScale called with a
+  /// scale of 1.0 / GetDeviceScale(). For example, if the view resource passed
+  /// to DidChangeView has a rectangle of (w=200, h=100) and a device scale of
+  /// 2.0, one would call Create with a size of (w=400, h=200) and then call
+  /// SetScale with 0.5. One would then treat each pixel in the context as a
+  /// single device pixel.
+  ///
+  /// @param[in] scale The scale to apply when painting.
+  ///
+  /// @return Returns <code>true</code> on success or <code>false</code>
+  /// if the resource is invalid or the scale factor is 0 or less.
+  bool SetScale(float scale);
+
+  /// GetScale() gets the scale factor that will be applied when painting the
+  /// graphics context onto the output device.
+  ///
+  /// @return Returns the scale factor for the graphics context. If the resource
+  /// is invalid, 0.0 will be returned. The default scale for a graphics context
+  /// is 1.0.
+  float GetScale();
+
  private:
   Size size_;
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_GRAPHICS_2D_H_