[analyzer] Use getParentIgnoreParenCasts instead of doing it by hand.

Apart from being more compact and already implemented, this also handles the
case where the parent is null. (It does also ignore all casts, not just
implicit ones, but this is more efficient to test and in the case we care
about---a message in a PseudoObjectExpr---there should only be implicit casts
anyway.

This should fix our internal buildbot.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191094 91177308-0d34-0410-b5e6-96231b3b80d8
Use -fms-compatibility to trigger lookup into dep. bases

Update the docs for -fms-extensions and -fms-compatibility to try to
clarify the difference between the two.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191095 91177308-0d34-0410-b5e6-96231b3b80d8
Clarify that we silently ignore some MS extensions like IDL attributes

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191096 91177308-0d34-0410-b5e6-96231b3b80d8
Fix ReST links I just added to the manual

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191097 91177308-0d34-0410-b5e6-96231b3b80d8
Update -fmsc-version docs for r190908, which set the default to 1700

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191098 91177308-0d34-0410-b5e6-96231b3b80d8
clang-cl: implement custom search for cl.exe in /fallback mode

This solves the problem of fallback onto ourselves if clang-cl
has been renamed to cl.exe and put on the PATH, as happens with
the VS integration.

Differential Revision: http://llvm-reviews.chandlerc.com/D1731

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191099 91177308-0d34-0410-b5e6-96231b3b80d8