TestRunner changes to allow RenderView change in the same process

When ProactivelySwapBrowsingInstance is turned on with the level set to
CrossSiteReuseProcess (see crrev.com/c/2043521), renderer-initiated
navigations might trigger a BrowsingInstance swap which leads to a
RenderView swap, etc, with a possibility of the current renderer process
getting reused. Some parts of the TestRunner code does not expect this
(they expect the main window RenderView change always go hand-in-hand
with RenderProcess change, and that we always restart with a clean state
after those navigations), so we are updating it.

Bug: 977562
Change-Id: I469d28b2553b1a7d4e8025c30c3a5593267cb42a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2094480
Commit-Queue: Rakina Zata Amni <rakina@chromium.org>
Reviewed-by: Alex Moshchuk <alexmos@chromium.org>
Reviewed-by: Łukasz Anforowicz <lukasza@chromium.org>
Cr-Commit-Position: refs/heads/master@{#751564}

content/shell/browser/web_test/blink_test_controller.cc

@@ -435,6 +435,7 @@ bool BlinkTestController::PrepareForWebTest(const TestInfo& test_info) {
   render_process_host_observer_.RemoveAll();
   all_observed_render_process_hosts_.clear();
   main_window_render_process_hosts_.clear();
+  main_window_render_view_hosts_.clear();
   accumulated_web_test_runtime_flags_changes_.Clear();
   blink_test_control_map_.clear();
   web_test_control_map_.clear();
@@ -1003,6 +1004,7 @@ void BlinkTestController::DiscardMainWindow() {
 
 void BlinkTestController::HandleNewRenderFrameHost(RenderFrameHost* frame) {
   RenderProcessHost* process_host = frame->GetProcess();
+  RenderViewHost* view_host = frame->GetRenderViewHost();
   bool main_window =
       WebContents::FromRenderFrameHost(frame) == main_window_->web_contents();
 
@@ -1013,9 +1015,19 @@ void BlinkTestController::HandleNewRenderFrameHost(RenderFrameHost* frame) {
       current_pid_ = process.Pid();
   }
 
-  // Is this the 1st time this renderer contains parts of the main test window?
+  // If this the first time this renderer contains parts of the main test
+  // window, we need to make sure that it gets configured correctly (including
+  // letting it know that it's part of the main test window).
+  // We consider the renderer as new when we see either a new RenderProcessHost
+  // or a new RenderViewHost, as it is possible that a new renderer (with a new
+  // RenderViewHost) reuses a renderer process, and it's also possible that we
+  // reuse RenderViewHosts (in some fetch tests).
+  // TODO(rakina): Understand the fetch tests to figure out if it's possible to
+  // remove RenderProcessHost tracking here.
   if (main_window &&
-      !base::Contains(main_window_render_process_hosts_, process_host)) {
+      (!base::Contains(main_window_render_view_hosts_, view_host) ||
+       !base::Contains(main_window_render_process_hosts_, process_host))) {
+    main_window_render_view_hosts_.insert(view_host);
     main_window_render_process_hosts_.insert(process_host);
 
     // Make sure the new renderer process_host has a test configuration shared

content/shell/browser/web_test/blink_test_controller.h

@@ -327,6 +327,7 @@ class BlinkTestController : public WebContentsObserver,
       render_process_host_observer_{this};
   std::set<RenderProcessHost*> all_observed_render_process_hosts_;
   std::set<RenderProcessHost*> main_window_render_process_hosts_;
+  std::set<RenderViewHost*> main_window_render_view_hosts_;
 
   // Changes reported by OnWebTestRuntimeFlagsChanged that have accumulated
   // since PrepareForWebTest (i.e. changes that need to be send to a fresh

content/shell/test_runner/test_runner.cc

@@ -1817,9 +1817,10 @@ void TestRunner::AddLoadingFrame(blink::WebFrame* frame) {
 }
 
 void TestRunner::RemoveLoadingFrame(blink::WebFrame* frame) {
-  if (!IsFramePartOfMainTestWindow(frame))
-    return;
-
+  // Note that unlike AddLoadingFrame, we don't check if |frame| is part of the
+  // current main test window or not, because in some cases we might have
+  // marked the new page as the current main test window before we removed all
+  // the loading frames of the old main test window from |loading_frames_|.
   if (!base::Contains(loading_frames_, frame))
     return;