WIP GPU scheduler + delayed activation / tile draw

gpu/command_buffer/common/sync_token.h

Index: gpu/command_buffer/common/sync_token.h
diff --git a/gpu/command_buffer/common/sync_token.h b/gpu/command_buffer/common/sync_token.h
index 6a6bfad2a9a8ba2ef8ebcfdea5ba3cf26151ab2c..ad8233c09586265f27ee3ef28ee8f2124758c681 100644
--- a/gpu/command_buffer/common/sync_token.h
+++ b/gpu/command_buffer/common/sync_token.h
@@ -51,9 +51,7 @@ struct GPU_EXPORT SyncToken {
     release_count_ = 0;
   }
 
-  void SetVerifyFlush() {
-    verified_flush_ = true;
-  }
+  void SetVerifyFlush() { verified_flush_ = true; }
 
   bool HasData() const {
     return namespace_id_ != CommandBufferNamespace::INVALID;
@@ -65,6 +63,12 @@ struct GPU_EXPORT SyncToken {
     return reinterpret_cast<const int8_t*>(this);
   }
 
+  bool IsEqual(const SyncToken& other) const {
+    return namespace_id_ == other.namespace_id() &&
+           command_buffer_id_ == other.command_buffer_id() &&
+           release_count_ == other.release_count();
+  }
+
   bool verified_flush() const { return verified_flush_; }
   CommandBufferNamespace namespace_id() const { return namespace_id_; }
   CommandBufferId command_buffer_id() const { return command_buffer_id_; }