commit 321b6ea1a1e2f392c629e2f074ae509a3aaefc42
author kouhei <kouhei@chromium.org> Fri Apr 28 03:57:48 2017
committer Commit bot <commit-bot@chromium.org> Fri Apr 28 03:57:48 2017
tree 4bc6513b691584301283209293d7d94bcbc108dd
parent fa0a7e66dd1583ab71436f26ee362278437e1972

[ES6 modules] Return previous error when an instantiation is reattempt.

Before this CL, when instantiation was reattempt for previously errored module,
ModuleTreeLinker::Instantiate() crashed.

This CL updates the code to follow whatwg/html update:
https://github.com/whatwg/html/pull/2559
so that we rethrow previous error when instantiation is reattempt.
TEST=webkit_unit_test --gtest_filter=ModuleTreeLinkerTest.FetchTreePreviousInstantiationFailure
BUG=594639,714521

Review-Url: https://codereview.chromium.org/2839563002
Cr-Commit-Position: refs/heads/master@{#467882}