Return a std::unique_ptr from getBufferForFile. NFC.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@216476 91177308-0d34-0410-b5e6-96231b3b80d8
Ignore -fdevirtualize and -fdevirtualize-speculatively for gcc compat

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@216477 91177308-0d34-0410-b5e6-96231b3b80d8
Return a std::unique_ptr from getBufferForFile. NFC.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@216478 91177308-0d34-0410-b5e6-96231b3b80d8
Fix an incorrect assert condition added in r216410.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@216479 91177308-0d34-0410-b5e6-96231b3b80d8
[libclang] Fixup the cursor spelling range for C++ destructors, operator overloads, and conversion functions.

Patch by Craig Tenenbaum!

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@216480 91177308-0d34-0410-b5e6-96231b3b80d8