Revert 80472 - GTTF: Detect browser crashes on shutdown in UI tests.Previously the automation fra...

Revert 80472 - GTTF: Detect browser crashes on shutdown in UI tests.Previously the automation framework could miss a browsercrash during shutdown on POSIX (on Windows there iscrash_service.exe that should catch all crashes).This change makes the automation framework avoid losinginformation about the browser process' exit status(CrashAwareSleep), and fixes a bug in base::WaitForExitCodeWithTimeout(which on POSIX never reported the process has been signaled).Finally, it makes the automation framework use WaitForExitCodeWithTimeoutinstead of WaitForSingleProcess. This way we can get the exit statusinformation in an accurate and cross-platform way.To avoid trying to close the same process handle twice (it's only an issue on Windows) I've changed WaitForExitCodeWithTimeout not to close the passed handle. It's only used in few places and I think this CL fixes all of them.I've tested this change locally on Mac with a UI test that SIGKILLs the browser.Before this change the test passed (it shouldn't), and after this changethe test failed with an information that the browser has not exited cleanly.BUG=56644
Review URL: http://codereview.chromium.org/6689014
TBR=phajdan.jr@chromium.org

[----------] 1 test from MultipartResponseUITest
[ RUN      ] MultipartResponseUITest.SingleVisit
[3538:3538:0405/104633:11326126024137:ERROR:process_util_posix.cc(108)] Received signal 11
	base::debug::StackTrace::StackTrace() [0xcd194a]
	base::(anonymous namespace)::StackDumpSignalHandler() [0xcb0e5a]
	0x2b835e391100
	AutomationProxy::GetBrowserWindowCount() [0x2055e86]
	ProxyLauncher::IsBrowserRunning() [0xc3f1a2]
	ProxyLauncher::QuitBrowser() [0xc454b3]
	ProxyLauncher::CloseBrowserAndServer() [0xc472d6]
	UITestBase::TearDown() [0xc50d54]
	UITest::TearDown() [0xc51260]
	testing::TestInfo::Run() [0xe8de78]
	testing::TestCase::Run() [0xe8df35]
	testing::internal::UnitTestImpl::RunAllTests() [0xe8f6e7]
	testing::internal::HandleSehExceptionsInMethodIfSupported<>() [0xe804d5]
	testing::internal::HandleExceptionsInMethodIfSupported<>() [0xe8ba92]
	testing::UnitTest::Run() [0xe8badb]
	base::TestSuite::Run() [0x212c26d]
	main [0xc48e41]
	0x2b835e37d1c4
	0x42fec9
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=80488