Update remaining files to use WeakPtr<T>::get() instead of "operator T*"

gpu/command_buffer/service/context_group.cc

Index: gpu/command_buffer/service/context_group.cc
diff --git a/gpu/command_buffer/service/context_group.cc b/gpu/command_buffer/service/context_group.cc
index 1b325ef20eaf51e67471be016012b0abc6aa5800..48ba2f300860f8528117087e49ee8d8c08a453c3 100644
--- a/gpu/command_buffer/service/context_group.cc
+++ b/gpu/command_buffer/service/context_group.cc
@@ -239,7 +239,7 @@ bool ContextGroup::Initialize(
 namespace {
 
 bool IsNull(const base::WeakPtr<gles2::GLES2Decoder>& decoder) {
-  return !decoder;
+  return !decoder.get();
 }
 
 }  // namespace anonymous
@@ -313,7 +313,7 @@ uint32 ContextGroup::GetMemRepresented() const {
 
 void ContextGroup::LoseContexts(GLenum reset_status) {
   for (size_t ii = 0; ii < decoders_.size(); ++ii) {
-    if (decoders_[ii]) {
+    if (decoders_[ii].get()) {
       decoders_[ii]->LoseContext(reset_status);
     }
   }