Add support for ES3 MSAA.

src/gpu/gl/GrGLCaps.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef GrGLCaps_DEFINED
 #define GrGLCaps_DEFINED
@@ skipping 36 matching lines @@
     /**
      * The type of MSAA for FBOs supported. Different extensions have different
      * semantics of how / when a resolve is performed.
      */
     enum MSFBOType {
         /**
          * no support for MSAA FBOs
          */
         kNone_MSFBOType = 0,
         /**
-         * GL3.0-style MSAA FBO (GL_ARB_framebuffer_object)
+         * GL3.0-style MSAA FBO (GL_ARB_framebuffer_object). 
          */
         kDesktop_ARB_MSFBOType,
         /**
          * earlier GL_EXT_framebuffer* extensions
          */
         kDesktop_EXT_MSFBOType,
         /**
+         * Similar to kDesktop_ARB but with additional restrictions on glBlitFramebuffer.
+         */
+        kES_3_0_MSFBOType,
+        /**
          * GL_APPLE_framebuffer_multisample ES extension
          */
         kES_Apple_MSFBOType,
         /**
          * GL_IMG_multisampled_render_to_texture. This variation does not have MSAA renderbuffers.
          * Instead the texture is multisampled when bound to the FBO and then resolved automatically
          * when read. It also defines an alternate value for GL_MAX_SAMPLES (which we call
          * GR_GL_MAX_SAMPLES_IMG).
          */
         kES_IMG_MsToTexture_MSFBOType,
@@ skipping 284 matching lines @@
     bool fFragCoordsConventionSupport : 1;
     bool fVertexArrayObjectSupport : 1;
     bool fUseNonVBOVertexAndIndexDynamicData : 1;
     bool fIsCoreProfile : 1;
     bool fDiscardFBSupport : 1;
 
     typedef GrDrawTargetCaps INHERITED;
 };
 
 #endif