Change dont_embed_build_metadata default to 1 except for Official build and fix some unittests.

base/build_time.cc

Index: base/build_time.cc
diff --git a/base/build_time.cc b/base/build_time.cc
index 86503e22a9f0400fa0828a3c4de4f0140767af14..b8b42966908fb47e696f01a2709bb9a90f2bd448 100644
--- a/base/build_time.cc
+++ b/base/build_time.cc
@@ -16,7 +16,7 @@ Time GetBuildTime() {
   //
   // __DATE__ is exactly "Mmm DD YYYY".
   // __TIME__ is exactly "hh:mm:ss".
-#if defined(DONT_EMBED_BUILD_METADATA)
+#if defined(DONT_EMBED_BUILD_METADATA) && !defined(OFFICIAL_BUILD)
   const char kDateTime[] = "Sep 02 2008 08:00:00 PST";
 #else
   const char kDateTime[] = __DATE__ " " __TIME__ " PST";