Added SetLayerTransform to PPAPI

ppapi/api/ppb_graphics_2d.idl

 /* 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.
  */
 
 /**
  * Defines the <code>PPB_Graphics2D</code> struct representing a 2D graphics
  * context within the browser.
  */
 
 [generate_thunk]
 
 label Chrome {
   M14 = 1.0,
   M27 = 1.1

[piman, 2016/04/15 19:24:39]

I believe you need to add a version here, M52 I believe.

[alessandroa, 2016/04/21 15:39:22]

Done.

 };
 
 /**
  * <code>PPB_Graphics2D</code> defines the interface for a 2D graphics context.
  */
 [macro="PPB_GRAPHICS_2D_INTERFACE"]
 interface PPB_Graphics2D {
   /**
    * Create() creates a 2D graphics context. The returned graphics context will
    * not be bound to the module instance on creation (call BindGraphics() on
@@ skipping 249 matching lines @@
    *
    * @param[in] resource A <code>Graphics2D</code> context resource.
    *
    * @return Returns the scale factor for the graphics context. If the resource
    * is not a valid <code>Graphics2D</code> context, this will return 0.0.
    */
   [version=1.1]
   float_t GetScale(
       [in] PP_Resource resource);
 
+  /**
+   * SetLayerTransform() sets a transformation factor that will be applied for
+   * the current graphics context displayed on the output device.  If both
+   * SetScale and SetLayerTransform will be used, they are going to get combined
+   * for the final result.
+   * This function has no effect until you call Flush().
+   * @param[in] scale The scale to be applied.
+   * @param[in] origin The origin of the scale.
+   * @param[in] translate The translation to be applied.
+   *
+   * @return Returns <code>true</code> on success or <code>false</code>

[piman, 2016/04/15 19:24:39]

nit: PP_TRUE, PP_FALSE instead of true, false.

[alessandroa, 2016/04/21 15:39:22]

Done.

+   * if the resource is invalid or the scale factor is 0 or less.
+   */
+  [version=1.2]
+  PP_Bool SetLayerTransform(
+      [in] PP_Resource resource,
+      [in] float_t scale,
+      [in] PP_Point origin,
+      [in] PP_Point translate);
 };