Add libclang hook 'clang_toggleCrashRecovery()', which provides a mechanism for a client to enable/disable CrashRecovery within libclang function calls.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@127920 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
index 88b3d76..502ee99 100644
--- a/tools/libclang/CIndex.cpp
+++ b/tools/libclang/CIndex.cpp
@@ -2309,6 +2309,13 @@
     delete static_cast<CIndexer *>(CIdx);
 }
 
+void clang_toggleCrashRecovery(unsigned isEnabled) {
+  if (isEnabled)
+    llvm::CrashRecoveryContext::Enable();
+  else
+    llvm::CrashRecoveryContext::Disable();
+}
+  
 CXTranslationUnit clang_createTranslationUnit(CXIndex CIdx,
                                               const char *ast_filename) {
   if (!CIdx)