WebGL 2: make sure VertexAttrib type match the corresponding attrib type in shader

gpu/command_buffer/service/vertex_attrib_manager.cc

Index: gpu/command_buffer/service/vertex_attrib_manager.cc
diff --git a/gpu/command_buffer/service/vertex_attrib_manager.cc b/gpu/command_buffer/service/vertex_attrib_manager.cc
index 76883dc0f3fe2e956e9017ea82970d0b407e3fb1..327f178f11ee391d57b06e08f229146cd9b8bdab 100644
--- a/gpu/command_buffer/service/vertex_attrib_manager.cc
+++ b/gpu/command_buffer/service/vertex_attrib_manager.cc
@@ -127,6 +127,8 @@ VertexAttribManager::~VertexAttribManager() {
 void VertexAttribManager::Initialize(uint32_t max_vertex_attribs,
                                      bool init_attribs) {
   vertex_attribs_.resize(max_vertex_attribs);
+  attrib_base_type_mask_ = 0u;
+  attrib_written_mask_ = 0u;
 
   for (uint32_t vv = 0; vv < vertex_attribs_.size(); ++vv) {
     vertex_attribs_[vv].set_index(vv);
@@ -146,6 +148,11 @@ bool VertexAttribManager::Enable(GLuint index, bool enable) {
   if (index >= vertex_attribs_.size()) {
     return false;
   }
+
+  if (!enable) {
+    attrib_written_mask_ &= ~(0x3 << (index * 2));
+  }
+
   VertexAttrib& info = vertex_attribs_[index];
   if (info.enabled() != enable) {
     info.set_enabled(enable);