Crashes about 50% of the time, testing locally on Linux trunk build.

$ webkit_unit_tests --gtest_filter=HTMLMediaElementEventListenersTest.FullscreenDetectorTimerCancelledOnContextDestroy
...
../../third_party/WebKit/Source/core/html/HTMLMediaElementEventListenersTest.cpp:171: Failure
Value of: observedResults.size()
  Actual: 0
Expected: 1u
Which is: 1
../../build/linux/debian_wheezy_amd64-sysroot/usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/debug/vector:313:
    error: attempt to subscript container with out-of-bounds index 0, but     
    container only holds 0 elements.

Objects involved in the operation:
sequence "this" @ 0x0x7fff980c6a00 {
}
Received signal 6
#0 0x7f747287dbbb base::debug::StackTrace::StackTrace()
#1 0x7f747287c24c base::debug::StackTrace::StackTrace()
#2 0x7f747287d6cf base::debug::(anonymous namespace)::StackDumpSignalHandler()
#3 0x7f74731b8330 <unknown>
#4 0x7f7460f0ec37 gsignal
#5 0x7f7460f12028 abort
#6 0x7f746134cfe5 __gnu_debug::_Error_formatter::_M_error()
#7 0x000000cde18c std::__debug::vector<>::operator[]()
#8 0x000000cdc46e blink::HTMLMediaElementEventListenersTest_FullscreenDetectorTimerCancelledOnContextDestroy_Test::TestBody()
...
1 test crashed:
    HTMLMediaElementEventListenersTest.FullscreenDetectorTimerCancelledOnContextDestroy (../../third_party/WebKit/Source/core/html/HTMLMediaElementEventListenersTest.cpp:133)