Move HiDPI-related Pepper interfaces to stable

This adds the APIs provided in PPB_View_Dev_0_1 and PP_Graphics2D_Dev_0_1 to
the public Pepper APIs for PPB_View and PPB_Graphics2D.

Includes:
- Change to IDL and generated C headers/shim
- Change to PPAPI to export the 1_1 interfaces
- C++ glue
- Example PPAPI plugin for using HiDPI Pepper APIs

BUG=144071
TEST=Existing (prebuilt) PDF plugin using 1.0 interfaces still works

Review URL: https://codereview.chromium.org/12989006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@193110 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 73 insertions, 2 deletions

diff --git a/ppapi/api/ppb_graphics_2d.idl b/ppapi/api/ppb_graphics_2d.idl
index 1dddc65..f9b420d 100644
--- a/ppapi/api/ppb_graphics_2d.idl
+++ b/ppapi/api/ppb_graphics_2d.idl
@@ -9,7 +9,8 @@
  */
 
 label Chrome {
-  M14 = 1.0
+  M14 = 1.0,
+  M27 = 1.1
 };
 
 /**
@@ -242,5 +243,41 @@ interface PPB_Graphics2D {
   int32_t Flush(
       [in] PP_Resource graphics_2d,
       [in] PP_CompletionCallback callback);
+
+  /**
+   * 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] resource A <code>Graphics2D</code> context resource.
+   * @param[in] scale The scale to apply when painting.
+   *
+   * @return Returns <code>PP_TRUE</code> on success or <code>PP_FALSE</code> if
+   * the resource is invalid or the scale factor is 0 or less.
+   */
+  [version=1.1]
+  PP_Bool SetScale(
+      [in] PP_Resource resource,
+      [in] float_t scale);
+
+  /***
+   * GetScale() gets the scale factor that will be applied when painting the
+   * graphics context onto the output device.
+   *
+   * @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);
+
 };
 
diff --git a/ppapi/api/ppb_view.idl b/ppapi/api/ppb_view.idl
index cc61ed2..a01c5e8 100644
--- a/ppapi/api/ppb_view.idl
+++ b/ppapi/api/ppb_view.idl
@@ -11,7 +11,8 @@
 [generate_thunk]
 
 label Chrome {
-  M18 = 1.0
+  M18 = 1.0,
+  M28 = 1.1
 };
 
 /**
@@ -159,5 +160,38 @@ interface PPB_View {
    */
   PP_Bool GetClipRect([in] PP_Resource resource,
                       [out] PP_Rect clip);
+
+  /**
+   * GetDeviceScale returns the scale factor between device pixels and Density
+   * Independent Pixels (DIPs, also known as logical pixels or UI pixels on
+   * some platforms). This allows the developer to render their contents at
+   * device resolution, even as coordinates / sizes are given in DIPs through
+   * the API.
+   *
+   * Note that the coordinate system for Pepper APIs is DIPs. Also note that
+   * one DIP might not equal one CSS pixel - when page scale/zoom is in effect.
+   *
+   * @param[in] resource A <code>PP_Resource</code> corresponding to a
+   * <code>PPB_View</code> resource.
+   *
+   * @return A <code>float</code> value representing the number of device pixels
+   * per DIP. If the resource is invalid, the value will be 0.0.
+   */
+  [version=1.1]
+  float_t GetDeviceScale([in] PP_Resource resource);
+
+  /**
+   * GetCSSScale returns the scale factor between DIPs and CSS pixels. This
+   * allows proper scaling between DIPs - as sent via the Pepper API - and CSS
+   * pixel coordinates used for Web content.
+   *
+   * @param[in] resource A <code>PP_Resource</code> corresponding to a
+   * <code>PPB_View</code> resource.
+   *
+   * @return css_scale A <code>float</code> value representing the number of
+   * DIPs per CSS pixel. If the resource is invalid, the value will be 0.0.
+   */
+  [version=1.1]
+  float_t GetCSSScale([in] PP_Resource resource);
 };