Add NaCl smoke test to browser_tests.

Add NaCl smoke test to browser_tests.

The smoke test is simple - it checks that Chrome can load nexes. The more
interesting part of this CL is that it lays the groundwork for adding more NaCl
tests to browser_tests. This will allow many nacl_integration tests to be
rewritten as browser_tests. This CL adds an extensible jig for decoding
messages from Javascript, which makes it easier to add test logic in the web
page. This CL also establishes locations in the build directory for nexes and
other test data.

There are two followup CLs planned: 1) simplify how nexes are built in GYP
and 2) share the code for running tests in Javascript with the PPAPI test
suite.

This is a recommit of r151716 with Linux ASAN tests disabled and GYP tweaks for
VS2010.

BUG= http://code.google.com/p/nativeclient/issues/detail?id=2959
TEST= browser_tests --gtest_filter=NaClBrowserTest*

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=151963

[Nick Bray (chromium), 2012-08-16 16:53:22]

Here's a re-spin of the CL you reverted.

All that has changed is an ifdef around the test definitions and a bogus input
for manifest generation in the gyp file.  Optional try bots seems happy.

http://codereview.chromium.org/10837207/

[brettw, 2012-08-16 20:18:52]

lgtm