Revert of Add ScopedTaskEnvironment::ExecutionControlMode. (patchset #6 id:100001 of https://codereview.chromium.org/2891363005/ )
Reason for revert:
Is causing consistent test failures on the main waterfall in net_unittests URLRequestSimpleJobTest.CancelAfterFirstReadStarted, for example:
https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Fchromium.mac%2FMac10.9_Tests%2F41620%2F%2B%2Frecipes%2Fsteps%2Fnet_unittests%2F0%2Flogs%2FURLRequestSimpleJobTest.CancelAfterFirstReadStarted%2F0
[1130:771:0523/094643.091773:30621298248173:FATAL:scoped_task_environment.cc(178)] Check failed: !task_queue_empty_closure_.
0 net_unittests 0x0000000102d4603c base::debug::StackTrace::StackTrace(unsigned long) + 28
1 net_unittests 0x0000000102d5db70 logging::LogMessage::~LogMessage() + 224
2 net_unittests 0x000000010302df97 base::test::ScopedTaskEnvironment::RunUntilIdle() + 183
3 net_unittests 0x000000010205f824 net::URLRequestSimpleJobTest_CancelAfterFirstReadStarted_Test::TestBody() + 260
4 net_unittests 0x00000001022adf56 testing::Test::Run() + 246
5 net_unittests 0x00000001022ae9f0 testing::TestInfo::Run() + 288
6 net_unittests 0x00000001022aef57 testing::TestCase::Run() + 263
7 net_unittests 0x00000001022b5057 testing::internal::UnitTestImpl::RunAllTests() + 871
8 net_unittests 0x00000001022b4cc3 testing::UnitTest::Run() + 163
9 net_unittests 0x00000001030309b3 base::TestSuite::Run() + 163
10 net_unittests 0x000000010303e176 base::LaunchUnitTests(int, char**, base::Callback<int (), (base::internal::CopyMode)1, (base::internal::RepeatMode)1> const&) + 134
11 net_unittests 0x0000000101fdf008 main + 440
12 libdyld.dylib 0x00007fff8d4495fd start + 1
13 ??? 0x0000000000000007 0x0 + 7
Original issue's description:
> Add ScopedTaskEnvironment::ExecutionControlMode.
>
> This enum controls whether tasks posted within the scope of a
> ScopedTaskEnvironment can run as they are posted or have to wait
> until a call to RunUntilIdle() to run.
>
> BUG=724077
> TBR=gab@chromium.org
>
> Review-Url: https://codereview.chromium.org/2891363005
> Cr-Commit-Position: refs/heads/master@{#473925}
> Committed: https://chromium.googlesource.com/chromium/src/+/fc7b5ec521b29a97e63a7cda5921aa5ed793679a
TBR=gab@chromium.org,robliao@chromium.org,fdoray@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=724077
Review-Url: https://codereview.chromium.org/2903633003
Cr-Commit-Position: refs/heads/master@{#473950}
8 files changed
