commit 5486a48109bd315c354cfe26f09f0881f2b95013
author John Stalcup <stalcup@google.com> Tue Sep 30 11:44:09 2014 -0700
committer John Stalcup <stalcup@google.com> Tue Sep 30 11:44:09 2014 -0700
tree c1d57cfc7cbb83c6e0790a5143055f233b84d069
parent ab4f599ce1d0d34051da02749b4b068532c78efc

Makes SDM MinimalRebuildCache updates transactional.

When SDM invokes incremental compiles it takes care to pass the proper
MinimalRebuildCache instance (for the current binding properties) to
the Compiler, and the Compiler updates the cache in place.

But if the compile failed it was possible for the cache to be left in
an inconsistent state (for example having already had some entries
removed but not yet had them rebuilt).

This change teaches SDM to always pass the Compiler a copy of the
current known-good MinimalRebuildCache and only replace its copy with
a modified one after a successful compile. This way whenever a compile
starts it will always be starting with a known good MinimalRebuildCache
instance.

Change-Id: I1d536c01746f6ede846cf0ddc519267f3809b6df
Review-Link: https://gwt-review.googlesource.com/#/c/9360/