Rename the AST file's SOURCE_LOCATION_MAP to MODULE_OFFSET_MAP, to indicate the greater role it will soon play in remapping.

llvm-svn: 136619
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index d8f6c6a..6521e7c 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -2271,7 +2271,7 @@
       break;
     }
 
-    case SOURCE_LOCATION_MAP: {
+    case MODULE_OFFSET_MAP: {
       // Additional remapping information.
       const unsigned char *Data = (const unsigned char*)BlobStart;
       const unsigned char *DataEnd = Data + BlobLen;