Replicating LayoutDumpFlags across OOPIFs.

content/shell/renderer/layout_test/blink_test_runner.cc

Index: content/shell/renderer/layout_test/blink_test_runner.cc
diff --git a/content/shell/renderer/layout_test/blink_test_runner.cc b/content/shell/renderer/layout_test/blink_test_runner.cc
index 13f30a302d973daf4c7a7e3b3b05c304fc53bff9..5eb43681081cbe9598fa825c7c20d26be358a47c 100644
--- a/content/shell/renderer/layout_test/blink_test_runner.cc
+++ b/content/shell/renderer/layout_test/blink_test_runner.cc
@@ -15,6 +15,7 @@
 #include "base/compiler_specific.h"
 #include "base/debug/debugger.h"
 #include "base/files/file_path.h"
+#include "base/guid.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/md5.h"
@@ -34,6 +35,7 @@
 #include "components/test_runner/layout_dump_flags.h"
 #include "components/test_runner/mock_screen_orientation_client.h"
 #include "components/test_runner/test_interfaces.h"
+#include "components/test_runner/tracked_dictionary.h"
 #include "components/test_runner/web_task.h"
 #include "components/test_runner/web_test_interfaces.h"
 #include "components/test_runner/web_test_proxy.h"
@@ -252,8 +254,8 @@ BlinkTestRunner::BlinkTestRunner(RenderView* render_view)
       focused_view_(NULL),
       is_main_window_(false),
       focus_on_next_commit_(false),
-      leak_detector_(new LeakDetector(this)) {
-}
+      leak_detector_(new LeakDetector(this)),
+      guid_(base::GenerateGUID()) {}
 
 BlinkTestRunner::~BlinkTestRunner() {
 }
@@ -610,6 +612,20 @@ void BlinkTestRunner::SetLocale(const std::string& locale) {
   setlocale(LC_ALL, locale.c_str());
 }
 
+void BlinkTestRunner::OnLayoutDumpFlagsChanged(
+    test_runner::LayoutDumpFlags* layout_dump_flags) {
+  // Ignore changes that happen before we got the initial, accumulated
+  // layout flag changes in ShellViewMsg_ReplicateTestConfiguration.
+  if (!is_main_window_)
+    return;
+
+  const base::DictionaryValue& changed_values =
+      layout_dump_flags->tracked_dictionary().changed_values();
+  Send(new ShellViewHostMsg_LayoutDumpFlagsChanged(routing_id(), changed_values,
+                                                   guid_));
+  layout_dump_flags->tracked_dictionary().ResetChangeTracking();
+}
+
 void BlinkTestRunner::TestFinished() {
   if (!is_main_window_ || !render_view()->GetMainRenderFrame()) {
     Send(new ShellViewHostMsg_TestFinishedInSecondaryRenderer(routing_id()));
@@ -896,8 +912,7 @@ void BlinkTestRunner::CaptureDump() {
     return;
   }
 
-  Send(
-      new ShellViewHostMsg_InitiateLayoutDump(routing_id(), layout_dump_flags));
+  Send(new ShellViewHostMsg_InitiateLayoutDump(routing_id()));
   // OnLayoutDumpCompleted will be eventually called by an IPC from the browser.
 }
 
@@ -969,7 +984,7 @@ void BlinkTestRunner::CaptureDumpComplete() {
                             new ShellViewHostMsg_TestFinished(routing_id())));
 }
 
-void BlinkTestRunner::OnReplicateTestConfiguration(
+void BlinkTestRunner::SetTestConfiguration(
     const ShellTestConfiguration& params) {
   test_config_ = params;
   is_main_window_ = true;
@@ -981,9 +996,19 @@ void BlinkTestRunner::OnReplicateTestConfiguration(
                                       params.enable_pixel_dumping);
 }
 
+void BlinkTestRunner::OnReplicateTestConfiguration(
+    const ShellTestConfiguration& params,
+    const base::DictionaryValue& accumulated_layout_dump_flags_changes) {
+  SetTestConfiguration(params);
+  LayoutTestRenderProcessObserver::GetInstance()
+      ->test_interfaces()
+      ->TestRunner()
+      ->ReplicateLayoutDumpFlagsChanges(accumulated_layout_dump_flags_changes);
+}
+
 void BlinkTestRunner::OnSetTestConfiguration(
     const ShellTestConfiguration& params) {
-  OnReplicateTestConfiguration(params);
+  SetTestConfiguration(params);
 
   ForceResizeRenderView(
       render_view(),
@@ -991,6 +1016,18 @@ void BlinkTestRunner::OnSetTestConfiguration(
   SetFocus(proxy_, true);
 }
 
+void BlinkTestRunner::OnReplicateLayoutDumpFlagsChanges(
+    const base::DictionaryValue& changed_layout_dump_flags,
+    const std::string& change_originator_guid) {
+  if (change_originator_guid == guid_)
+    return;

[Łukasz Anforowicz, 2016/03/03 21:46:34]

We want to avoid consuming change notification broadcasts in the renderer that
originated the change (otherwise the broadcast can clobber subsequent changes in
the originator).  This is done via |change_originator_guid| in the CL.

This results in 1 avoidable IPC from browser to renderer (but then
correctness>performance + this is just test code?).  Plus, I don’t know how to
do things more efficiently or cleanly:

- I don’t know how the browser can identify RPH associated with the sender (this
might be doable if the notification was a RFH rather than RVH message, but
renderer side inherently gets change notifications at RV level [AFAICT some flag
changes cannot be attributed to a specific frame]).

- I don’t know how the renderer could send its RPH->GetID in the payload (there
is no RP::GetID method).

+
+  LayoutTestRenderProcessObserver::GetInstance()
+      ->test_interfaces()
+      ->TestRunner()
+      ->ReplicateLayoutDumpFlagsChanges(changed_layout_dump_flags);
+}
+
 void BlinkTestRunner::OnSessionHistory(
     const std::vector<int>& routing_ids,
     const std::vector<std::vector<PageState>>& session_histories,