[turbofan] Fix JSInliner to handle non-returning bodies.

[turbofan] Fix JSInliner to handle non-returning bodies.

The assumption that every function body produces a value does not hold
for functions that e.g. unconditionally throw or endlessly loop. This
fixes the inlining logic to handle such cases.

R=bmeurer@chromium.org
TEST=mjsunit/regress/regress-crbug-530598
BUG=chromium:530598
LOG=n

Committed: https://crrev.com/9e47ec6edab84adcbd180d2e7fa03fcb2d9295ee
Cr-Commit-Position: refs/heads/master@{#30738}

[Michael Starzinger, 2015-09-15 09:44:15]

https://codereview.chromium.org/1333193005/diff/1/src/compiler/js-inlining.cc
File src/compiler/js-inlining.cc (right):

https://codereview.chromium.org/1333193005/diff/1/src/compiler/js-inlining.cc...
src/compiler/js-inlining.cc:212: ReplaceWithValue(call, call, call,
jsgraph_->Dead());
Ideally this could be a helper method on AdvancedReducer::Editor named something
like "ReplaceWithUnreachable" or similar. But I cannot imagine any valid use of
said method outside the JSInliner, hence I would prefer to leave it as it is for
now. Would that be fine with you?

[Benedikt Meurer, 2015-09-15 11:15:57]

LGTM.

[Michael Starzinger, 2015-09-15 11:17:08]

The CQ bit was checked by mstarzinger@chromium.org

[commit-bot: I haz the power, 2015-09-15 11:17:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1333193005/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1333193005/1

[commit-bot: I haz the power, 2015-09-15 11:19:10]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-15 11:19:30]

Patchset 1 (id:??) landed as
https://crrev.com/9e47ec6edab84adcbd180d2e7fa03fcb2d9295ee
Cr-Commit-Position: refs/heads/master@{#30738}