Update to Chromium revision 9cedf753 (#418732)

- Simplify usage of OnBeforePluginLoad (issue #2015)
- Switch crash reporting from crashpad to breakpad on Windows and OS X.
  Adds a new chrome_elf.dll dependency on Windows (issue #1995)
- Remove CefTextfield::GetPlaceholderTextColor() method which is no
  longer supported by Chromium.

libcef/browser/context.cc

@@ -31,7 +31,11 @@
 #include "ui/base/ui_base_switches.h"
 
 #if defined(OS_WIN)
+#include "chrome_elf/chrome_elf_main.h"
 #include "content/public/app/sandbox_helper_win.h"
+#include "components/crash/content/app/crash_switches.h"
+#include "components/crash/content/app/crashpad.h"
+#include "components/crash/content/app/run_as_crashpad_handler_win.h"
 #include "sandbox/win/src/sandbox_types.h"
 #endif
 
@@ -93,6 +97,11 @@ int CefExecuteProcess(const CefMainArgs& args,
   if (process_type.empty())
     return -1;
 
+#if defined(OS_WIN)
+  if (process_type == crash_reporter::switches::kCrashpadHandler)
+    return crash_reporter::RunAsCrashpadHandler(command_line);
+#endif
+
   CefMainDelegate main_delegate(application);
 
   // Execute the secondary process.
@@ -260,6 +269,11 @@ bool CefContext::Initialize(const CefMainArgs& args,
   }
 #endif
 
+#if defined(OS_WIN)
+  // Signal Chrome Elf that Chrome has begun to start.
+  SignalChromeElf();
+#endif
+
   main_delegate_.reset(new CefMainDelegate(application));
   main_runner_.reset(content::ContentMainRunner::Create());
   browser_info_manager_.reset(new CefBrowserInfoManager);