Bug 850681 - Part 9: Return early if possible during leak summary generation; r=ted

Now that we close the log file before summary generation (rather than at the
end of processSingleLeakFile()), we can return early in some cases during
leak summary generation.
Bug 850681 - Part 10: Tweak comments; r=ted
Bug 850681 - Part 11: Move processString to the message part of log lines & remove unhelpful process IDs; r=ted

Our standard logging format is:
TEST-{INFO,UNEXPECTED-FAIL} | testName | message

For leak logs from processes other than the main process (eg plugin processes),
currently processSingleLeakFile outputs:
TEST-{INFO,UNEXPECTED-FAIL} | foo process 123 | testName | message

This patch turns these into:
TEST-{INFO,UNEXPECTED-FAIL} | testName | foo process: message

Note: The process ID is contained in the raw leak log (which gets printed to the
log anyway), so we don't need to repeat it in the main summary log lines. In
addition, the variable process ID often breaks TBPL bug suggestions, so should
be avoided where possible.
Bug 827486, part 1: add JSImplementation extended attribute. r=bz
Bug 827486, part 2 - Refactor example class codegen into common base class. r=bz
Bug 827486, part 3 - add dependencies for CGBindingImplClass. r=bz
Bug 827486, part 4: copy parts of example generator to JS impl generator. r=bz
Bug 827486, part 5: add the main JS impl code gen. r=bz
Bug 827486, part 6 - generate headers and code for JS implemented WebIDL classes. r=bz
Bug 827486, part 7 - add basic code gen test. r=bz
[Bug 851972] Remove XPIDL for ComponentTransferFunctionElement r=Ms2ger
Bug 851981: Make loop iterator in mozalloc_handle_oom a size_t instead of an int, to fix build warning for signed/unsigned comparison. r=bsmedberg
Bug 845785 - re-exclude test_Range-mutations.html for frequent crashes, a=test-only
Bug 848538 - Push a cx before calling into ctypes callbacks. r=jorendorff
Fix OdinMonkey when --disable-ion (no bug, r=me)

--HG--
extra : rebase_source : 3536acf09aecbdcb2ca9156873fc39571328975a
Backed out changeset 7268c16cad16 (bug 829747) for causing B2G test timeouts; CLOSED TREE
Bug 848538 - Followup test bustage fix on a CLOSED TREE. r=me
Back out Bug 462463 for massively regressing pymake depend build speed. CLOSED TREE
Back out Bug 827486 for PGO bustage. CLOSED TREE
Merge backout on a CLOSED TREE.