clang-format: Option to removing the space before assignment operators.

Patch contributed by Aaron Wishnick. Thank you!

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@191375 91177308-0d34-0410-b5e6-96231b3b80d8
Don't pass -print-stats to the driver, it is a -cc1 option only.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@191376 91177308-0d34-0410-b5e6-96231b3b80d8
Move --relocatable-pch to Options.td.

It is a valid driver option (we have tests for that), so it should not be
marked as NoDriverOption.

No functionality change other than it showing in --help.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@191377 91177308-0d34-0410-b5e6-96231b3b80d8
Use -Xclang to pass -internal-isystem and -internal-externc-isystem to -cc1.

They are cc1 options only, so the driver was ignoring them.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@191379 91177308-0d34-0410-b5e6-96231b3b80d8
Produce an error if a -cc1 only option is passed to the driver.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@191380 91177308-0d34-0410-b5e6-96231b3b80d8