This CL adds --crankshaft and --no-always-opt flags to the tests that use
assertOptimized() and assertUnoptimized() respectively.
This CL also adds presubmit checks that ensure that tests have the proper
flags set.
BUG=v8:5890
Review-Url: https://codereview.chromium.org/2653753007
Cr-Commit-Position: refs/heads/master@{#42709}
The Crankshaft fast case for String.fromCharCode() unconditionally
deoptimizes on all non-int32 inputs, even tho it would be perfectly
valid to just truncate the index to an int32.
R=ishell@chromium.org
BUG=chromium:587068
LOG=n
Review URL: https://codereview.chromium.org/1727873003
Cr-Commit-Position: refs/heads/master@{#34243}