Merge "Revert "Fix absolute paths in clang debug output""

cc/config/clang.go

@@ -116,10 +116,6 @@ func init() {
 
 		// http://b/68236239 Allow 0/NULL instead of using nullptr everywhere.
 		"-Wno-zero-as-null-pointer-constant",
-
-		// http://b/36463318 Clang executes with an absolute path, so clang-provided
-		// headers are now absolute.
-		"-fdebug-prefix-map=$$PWD/=",
 	}, " "))
 
 	pctx.StaticVariable("ClangExtraCppflags", strings.Join([]string{