Command buffer: Fix bugs for drawing when the type of vertex attrib is a packed type

gpu/command_buffer/common/gles2_cmd_utils.cc

Index: gpu/command_buffer/common/gles2_cmd_utils.cc
diff --git a/gpu/command_buffer/common/gles2_cmd_utils.cc b/gpu/command_buffer/common/gles2_cmd_utils.cc
index 0011053ad2d63e0892e809baf6c74e1feb57d83b..713497f9ed3d362983b7be8c8fb075f5dba9df8b 100644
--- a/gpu/command_buffer/common/gles2_cmd_utils.cc
+++ b/gpu/command_buffer/common/gles2_cmd_utils.cc
@@ -795,7 +795,7 @@ uint32_t GLES2Util::GetElementCountForUniformType(int type) {
   }
 }
 
-size_t GLES2Util::GetGLTypeSizeForTexturesAndBuffers(uint32_t type) {
+size_t GLES2Util::GetGLTypeSizeForBuffers(uint32_t type) {
   switch (type) {
     case GL_BYTE:
       return sizeof(GLbyte);  // NOLINT
@@ -824,6 +824,13 @@ size_t GLES2Util::GetGLTypeSizeForTexturesAndBuffers(uint32_t type) {
   }
 }
 
+size_t GLES2Util::GetGroupSizeForBufferType(uint32_t count, uint32_t type) {
+  size_t type_size = GetGLTypeSizeForBuffers(type);
+  // For packed types, group size equals to the type size.
+  if (type == GL_INT_2_10_10_10_REV || type == GL_UNSIGNED_INT_2_10_10_10_REV)
+    return type_size;

[Zhenyao Mo, 2016/02/26 04:24:29]

nit: please DCHECK_EQ(4u, count) here.

[yunchao, 2016/02/26 06:45:26]

Done.

+  return type_size * count;
+}
 size_t GLES2Util::GetComponentCountForGLTransformType(uint32_t type) {
   switch (type) {
     case GL_TRANSLATE_X_CHROMIUM: