Update from https://crrev.com/311076

base/mac/foundation_util.h

Index: base/mac/foundation_util.h
diff --git a/base/mac/foundation_util.h b/base/mac/foundation_util.h
index 46ea3c324c3f39dd774030bf05a68250818321c7..accc0d9fe1080f25d4e9d04fb5d2d043ac3355b0 100644
--- a/base/mac/foundation_util.h
+++ b/base/mac/foundation_util.h
@@ -64,6 +64,15 @@ namespace mac {
 BASE_EXPORT bool AmIBundled();
 BASE_EXPORT void SetOverrideAmIBundled(bool value);
 
+#if defined(UNIT_TEST)
+// This is required because instantiating some tests requires checking the
+// directory structure, which sets the AmIBundled cache state. Individual tests
+// may or may not be bundled, and this would trip them up if the cache weren't
+// cleared. This should not be called from individual tests, just from test
+// instantiation code that gets a path from PathService.
+BASE_EXPORT void ClearAmIBundledCache();
+#endif
+
 // Returns true if this process is marked as a "Background only process".
 BASE_EXPORT bool IsBackgroundOnlyProcess();