Add support for GL_EXT_unpack_subimage

Review URL: http://codereview.appspot.com/5359048/



git-svn-id: http://skia.googlecode.com/svn/trunk@2654 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrGpuGLShaders.cpp b/src/gpu/GrGpuGLShaders.cpp
index 0961548..67b1c37 100644
--- a/src/gpu/GrGpuGLShaders.cpp
+++ b/src/gpu/GrGpuGLShaders.cpp
@@ -1001,7 +1001,7 @@
                 stage.fOptFlags |= StageDesc::kCustomTextureDomain_OptFlagBit;
             }
 
-            if (!this->glCaps().fTextureSwizzle) {
+            if (!this->glCaps().fTextureSwizzleSupport) {
                 if (GrPixelConfigIsAlphaOnly(texture->config())) {
                     // if we don't have texture swizzle support then
                     // the shader must do an alpha smear after reading