Now that all accesses to the last match info are in C++ and TF code, we can
finally turn the last match info into a FixedArray. Similar to the ArrayList,
it uses its first field to store its length and grows dynamically in amortized
O(1) time.
Unlike previously, this means that the last match info pointer stored on the
context can actually change (in case the FixedArray needs to grow).
BUG=v8:5339
Review-Url: https://codereview.chromium.org/2415103002
Cr-Commit-Position: refs/heads/master@{#40308}
Thrown exceptions must be handled before another exception is thrown.
This fixes all remaining test failures exposed by not clearing pending
exceptions in JSEntryStub.
BUG=v8:5259
Review-Url: https://codereview.chromium.org/2207923002
Cr-Commit-Position: refs/heads/master@{#38324}
