WebGL 2: Fix nits when check vertexAttrib type with variable type in vertex shader

gpu/command_buffer/service/context_state.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file contains the ContextState class.
 
 #ifndef GPU_COMMAND_BUFFER_SERVICE_CONTEXT_STATE_H_
 #define GPU_COMMAND_BUFFER_SERVICE_CONTEXT_STATE_H_
 
 #include <memory>
@@ skipping 229 matching lines @@
 
   ErrorState* GetErrorState();
 
   void SetBoundBuffer(GLenum target, Buffer* buffer);
   void RemoveBoundBuffer(Buffer* buffer);
 
   void InitGenericAttribBaseType(GLuint max_vertex_attribs) {
       max_vertex_attribs_ = max_vertex_attribs;
 
       uint32_t packed_size = max_vertex_attribs_ / 16;
       packed_size += (max_vertex_attribs_ % 16 == 0) ? 0 : 1;

[yunchao, 2016/07/22 17:32:24]

If you want to use ceil(), please don't forget to cast max_vertex_attribs_ or 16
to float. 

       generic_attrib_base_type_mask_.resize(packed_size);
       for (uint32_t i = 0; i < packed_size; ++i) {
-        generic_attrib_base_type_mask_[i] = 0xFFFFFFFF;
+        // All generic attribs are float type by default.
+        generic_attrib_base_type_mask_[i] = 0x55555555u * SHADER_VARIABLE_FLOAT;
       }
   }
 
   void SetGenericVertexAttribBaseType(GLuint index, GLenum base_type) {
     DCHECK(index < max_vertex_attribs_);
     int shift_bits = (index % 16) * 2;
     generic_attrib_base_type_mask_[index / 16] &= ~(0x3 << shift_bits);
     generic_attrib_base_type_mask_[index / 16] |= (base_type << shift_bits);
   }
 
@@ skipping 89 matching lines @@
 
   FeatureInfo* feature_info_;
   std::unique_ptr<ErrorState> error_state_;
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_CONTEXT_STATE_H_