Allow premultiply_alpha + unpremultiply_alpha in CopyTextureCHROMIUMResourceManager

gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc

Index: gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc b/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
index 30732b8ea0996c2168d104e26f857b41d793d814..f49592307623204612545a1cff539ad38791715b 100644
--- a/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
+++ b/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
@@ -37,9 +37,6 @@ enum FragmentShaderId {
 FragmentShaderId GetFragmentShaderId(bool premultiply_alpha,
                                      bool unpremultiply_alpha,
                                      GLenum target) {
-  // Only one alpha mode at a time makes sense.
-  DCHECK(!premultiply_alpha || !unpremultiply_alpha);
-
   enum {
     SAMPLER_2D,
     SAMPLER_RECTANGLE_ARB,
@@ -136,9 +133,6 @@ std::string GetVertexShaderSource() {
 std::string GetFragmentShaderSource(bool premultiply_alpha,
                                     bool unpremultiply_alpha,
                                     GLenum target) {
-  // Only one alpha mode at a time makes sense.
-  DCHECK(!premultiply_alpha || !unpremultiply_alpha);
-
   std::string source;
 
   // Preamble for core and compatibility mode.