MIPS: Fix BlockTrampolinePoolFor() to emit trampoline before blocking, if needed.

MIPS: Fix BlockTrampolinePoolFor() to emit trampoline before blocking, if needed.

Fixes possible failure in AssembleArchTableSwitch().

BUG=v8:4294
LOG=y

Committed: https://crrev.com/f0d1106a3fa1ffaa822efc90d61e2aca315cbe15
Cr-Commit-Position: refs/heads/master@{#29589}

[paul.l..., 2015-07-13 07:04:51]

paul.lind@imgtec.com changed reviewers:
+ balazs.kilvady@imgtec.com, bmeurer@chromium.org,
dusan.milosavljevic@imgtec.com, hablich@chromium.org

[paul.l..., 2015-07-13 07:04:51]

I put the test case in test-macro-assembler-mips rather than
test-run-machops/RunSwitch..., as the failure mode is very mips-specific. mips64
port still to come (in the morning).

[Benedikt Meurer, 2015-07-13 07:05:46]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2015-07-13 07:05:46]

lgtm

[commit-bot: I haz the power, 2015-07-13 07:05:56]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1229863004/1

[commit-bot: I haz the power, 2015-07-13 07:28:31]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-07-13 07:28:45]

Patchset 1 (id:??) landed as
https://crrev.com/f0d1106a3fa1ffaa822efc90d61e2aca315cbe15
Cr-Commit-Position: refs/heads/master@{#29589}