[test] Initial import of an emscripten test suite.

[test] Initial import of an emscripten test suite.

These tests are based on individual tests from the Emscripten benchmark
suite, which are used to test Emscripten itself. We adopt them to test
asm.js code paths in V8.

TBR=machenbach@chromium.org

Committed: https://crrev.com/bb346227dbff1a2281032878b21d4a4164d87480
Cr-Commit-Position: refs/heads/master@{#27962}

[Benedikt Meurer, 2015-04-21 12:11:20]

bmeurer@chromium.org changed reviewers:
+ machenbach@chromium.org

[Michael Achenbach, 2015-04-21 12:18:18]

machenbach@chromium.org changed reviewers:
+ machenbach@chromium.org

[Michael Achenbach, 2015-04-21 12:18:39]

machenbach@chromium.org changed reviewers:
+ machenbach@chromium.org

[commit-bot: I haz the power, 2015-04-22 00:21:52]

Patchset 1 (id:??) landed as
https://crrev.com/bb346227dbff1a2281032878b21d4a4164d87480
Cr-Commit-Position: refs/heads/master@{#27962}

[commit-bot: I haz the power, 2015-04-22 04:09:54]

Patchset 1 (id:??) landed as
https://crrev.com/bb346227dbff1a2281032878b21d4a4164d87480
Cr-Commit-Position: refs/heads/master@{#27962}