Try to diagnose blink reinitialisation in WebView.

content/renderer/in_process_renderer_thread.cc

Index: content/renderer/in_process_renderer_thread.cc
diff --git a/content/renderer/in_process_renderer_thread.cc b/content/renderer/in_process_renderer_thread.cc
index a2c8c5d4459b8e316f009617f03bbb87e9dccac5..b8770cefddd5b432bee85f86ebf8027450bfbc29 100644
--- a/content/renderer/in_process_renderer_thread.cc
+++ b/content/renderer/in_process_renderer_thread.cc
@@ -4,7 +4,9 @@
 
 #include "content/renderer/in_process_renderer_thread.h"
 
+#include "base/command_line.h"
 #include "build/build_config.h"
+#include "content/public/common/content_switches.h"
 #include "content/renderer/render_process.h"
 #include "content/renderer/render_process_impl.h"
 #include "content/renderer/render_thread_impl.h"
@@ -21,6 +23,13 @@ InProcessRendererThread::InProcessRendererThread(
 }
 
 InProcessRendererThread::~InProcessRendererThread() {
+#if defined(OS_ANDROID)
+  // Don't allow the render thread to be shut down in single process mode on
+  // Android. Temporary CHECK() to debug http://crbug.com/514141
+  CHECK(!base::CommandLine::ForCurrentProcess()->HasSwitch(

[johnme, 2016/04/19 14:25:10]

This check triggers frequently in content_browsertests:
https://build.chromium.org/p/tryserver.chromium.android/builders/linux_androi...

+      switches::kSingleProcess));
+#endif
+
   Stop();
 }
 
@@ -31,12 +40,23 @@ void InProcessRendererThread::Init() {
   // will not change the thread name kept in Java VM.
 #if defined(OS_ANDROID)
   base::android::AttachCurrentThreadWithName(thread_name());
+  // Make sure we aren't somehow reinitialising the inprocess renderer thread on
+  // Android. Temporary CHECK() to debug http://crbug.com/514141
+  CHECK(!base::CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kSingleProcess) || !render_process_);
 #endif
   render_process_.reset(new RenderProcessImpl());
   RenderThreadImpl::Create(params_);
 }
 
 void InProcessRendererThread::CleanUp() {
+#if defined(OS_ANDROID)
+  // Don't allow the render thread to be shut down in single process mode on
+  // Android. Temporary CHECK() to debug http://crbug.com/514141
+  CHECK(!base::CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kSingleProcess));
+#endif
+
   render_process_.reset();
 
   // It's a little lame to manually set this flag.  But the single process