Implement support for dual source blending in ES

src/gpu/gl/GrGLInterface.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "gl/GrGLInterface.h"
 #include "gl/GrGLExtensions.h"
@@ skipping 372 matching lines @@
     // buffer mapping was part of original VBO extension
     // which we require.
     if (kGL_GrGLStandard == fStandard || fExtensions.has("GL_OES_mapbuffer")) {
         if (NULL == fFunctions.fMapBuffer ||
             NULL == fFunctions.fUnmapBuffer) {
             RETURN_FALSE_INTERFACE
         }
     }
 
     // Dual source blending
-    if (kGL_GrGLStandard == fStandard &&
-        (glVer >= GR_GL_VER(3,3) || fExtensions.has("GL_ARB_blend_func_extended"))) {
-        if (NULL == fFunctions.fBindFragDataLocationIndexed) {
-            RETURN_FALSE_INTERFACE
+    if (kGL_GrGLStandard == fStandard) {
+        if (glVer >= GR_GL_VER(3,3) || fExtensions.has("GL_ARB_blend_func_extended")) {
+            if (NULL == fFunctions.fBindFragDataLocationIndexed) {
+                RETURN_FALSE_INTERFACE
+            }
+        }
+    } else {
+        if (glVer >= GR_GL_VER(3,0) && fExtensions.has("GL_EXT_blend_func_extended")) {
+            if (NULL == fFunctions.fBindFragDataLocation ||
+                NULL == fFunctions.fBindFragDataLocationIndexed) {
+                RETURN_FALSE_INTERFACE
+            }
         }
     }
 
+
     // glGetStringi was added in version 3.0 of both desktop and ES.
     if (glVer >= GR_GL_VER(3, 0)) {
         if (NULL == fFunctions.fGetStringi) {
             RETURN_FALSE_INTERFACE
         }
     }
 
     if (kGL_GrGLStandard == fStandard) {
         if (glVer >= GR_GL_VER(3, 0) || fExtensions.has("GL_ARB_vertex_array_object")) {
             if (NULL == fFunctions.fBindVertexArray ||
@@ skipping 290 matching lines @@
             NULL == fFunctions.fGetDebugMessageLog ||
             NULL == fFunctions.fPushDebugGroup ||
             NULL == fFunctions.fPopDebugGroup ||
             NULL == fFunctions.fObjectLabel) {
             RETURN_FALSE_INTERFACE
         }
     }
 
     return true;
 }