Replace source pointer in cc::CopyOutputRequest with a base::UnguessableToken

cc/layers/layer_unittest.cc

Index: cc/layers/layer_unittest.cc
diff --git a/cc/layers/layer_unittest.cc b/cc/layers/layer_unittest.cc
index d47561b0e190d6d53d3033aca98828f6b80b320d..9d9f8ccdd75f7a9bc8370841fd36c25045309213 100644
--- a/cc/layers/layer_unittest.cc
+++ b/cc/layers/layer_unittest.cc
@@ -84,6 +84,11 @@ namespace cc {
 
 namespace {
 
+static auto kArbitrarySourceId1 =
+    base::UnguessableToken::Deserialize(0xdead, 0xbeef);
+static auto kArbitrarySourceId2 =
+    base::UnguessableToken::Deserialize(0xdead, 0xbee0);
+
 class MockLayerTree : public LayerTree {
  public:
   MockLayerTree(LayerTreeHostInProcess::InitParams* params,
@@ -1346,19 +1351,19 @@ TEST_F(LayerTest, DedupesCopyOutputRequestsBySource) {
   result_count = 0;
 
   // Create identical requests, but this time the source is being set.  Expect
-  // the first request from |this| source aborts immediately when the second
-  // request from |this| source is made.
+  // the first request using |kArbitrarySourceId1| aborts immediately when
+  // the second request using |kArbitrarySourceId1| is made.
   int did_receive_first_result_from_this_source = 0;
   request = CopyOutputRequest::CreateRequest(base::Bind(
       &ReceiveCopyOutputResult, &did_receive_first_result_from_this_source));
-  request->set_source(this);
+  request->set_source(kArbitrarySourceId1);
   layer->RequestCopyOfOutput(std::move(request));
   EXPECT_EQ(0, did_receive_first_result_from_this_source);
   // Make a request from a different source.
   int did_receive_result_from_different_source = 0;
   request = CopyOutputRequest::CreateRequest(base::Bind(
       &ReceiveCopyOutputResult, &did_receive_result_from_different_source));
-  request->set_source(reinterpret_cast<void*>(0xdeadbee0));
+  request->set_source(kArbitrarySourceId2);
   layer->RequestCopyOfOutput(std::move(request));
   EXPECT_EQ(0, did_receive_result_from_different_source);
   // Make a request without specifying the source.
@@ -1367,11 +1372,11 @@ TEST_F(LayerTest, DedupesCopyOutputRequestsBySource) {
       &ReceiveCopyOutputResult, &did_receive_result_from_anonymous_source));
   layer->RequestCopyOfOutput(std::move(request));
   EXPECT_EQ(0, did_receive_result_from_anonymous_source);
-  // Make the second request from |this| source.
+  // Make the second request from |kArbitrarySourceId1|.
   int did_receive_second_result_from_this_source = 0;
   request = CopyOutputRequest::CreateRequest(base::Bind(
       &ReceiveCopyOutputResult, &did_receive_second_result_from_this_source));
-  request->set_source(this);
+  request->set_source(kArbitrarySourceId1);
   layer->RequestCopyOfOutput(
       std::move(request));  // First request to be aborted.
   EXPECT_EQ(1, did_receive_first_result_from_this_source);