The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/089bb9113baa5ada31c80fbb6353e0185a479e6e

commit 089bb9113baa5ada31c80fbb6353e0185a479e6e
Author: hiroshige <hiroshige@chromium.org>
Date: Thu Apr 27 20:43:15 2017

Insert CHECK()s to ensure module-related code are not executed without the flag

BUG=715376

Review-Url: https://codereview.chromium.org/2843873002
Cr-Commit-Position: refs/heads/master@{#467777}

[modify] https://crrev.com/089bb9113baa5ada31c80fbb6353e0185a479e6e/third_party/WebKit/Source/bindings/core/v8/ScriptModule.cpp
[modify] https://crrev.com/089bb9113baa5ada31c80fbb6353e0185a479e6e/third_party/WebKit/Source/bindings/core/v8/ScriptModule.h
[modify] https://crrev.com/089bb9113baa5ada31c80fbb6353e0185a479e6e/third_party/WebKit/Source/core/dom/ModulatorImpl.cpp

Done for "Ensure module scripts are fetched/executed only behind the flag".

I'll keep this open until module scripts are shipped without flag and the CHECK()s inserted are removed.

Changed to be blocked on 594639 as we need to ship modules first to resolve this bug.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/cdd575440f88c9d52e48cacf92eecbf226c363f9

commit cdd575440f88c9d52e48cacf92eecbf226c363f9
Author: Kouhei Ueno <kouhei@chromium.org>
Date: Tue Nov 07 06:45:48 2017

[ES6 modules] Retire module feature flag

This CL removes "features::kModuleScripts" flag and
"RuntimeEnabledFeatures::ModuleScriptsEnabled()", and enables codepaths
previously gated by the feature by default.

Bug: 715376
Change-Id: Ib9ccd3648daa503c2ac653c299496344e95afd42
Reviewed-on: https://chromium-review.googlesource.com/753266
Reviewed-by: Takashi Toyoshima <toyoshim@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Kouhei Ueno <kouhei@chromium.org>
Cr-Commit-Position: refs/heads/master@{#514415}
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/chrome/browser/about_flags.cc
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/chrome/browser/flag_descriptions.cc
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/chrome/browser/flag_descriptions.h
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/content/child/runtime_features.cc
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/content/public/common/content_features.cc
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/content/public/common/content_features.h
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/third_party/WebKit/Source/bindings/core/v8/ScriptModule.cpp
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/third_party/WebKit/Source/bindings/core/v8/V8Initializer.cpp
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/third_party/WebKit/Source/core/dom/ModulatorImplBase.cpp
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/third_party/WebKit/Source/core/dom/ScriptLoader.cpp
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/third_party/WebKit/Source/core/html/HTMLScriptElement.idl
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/third_party/WebKit/Source/platform/exported/WebRuntimeFeatures.cpp
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/third_party/WebKit/Source/platform/runtime_enabled_features.json5
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/third_party/WebKit/public/platform/WebRuntimeFeatures.h
[modify] https://crrev.com/cdd575440f88c9d52e48cacf92eecbf226c363f9/tools/metrics/histograms/enums.xml