Makes GetBuildTime behave identically on all build types.

base/build_time_unittest.cc

Index: base/build_time_unittest.cc
diff --git a/base/build_time_unittest.cc b/base/build_time_unittest.cc
index aac64a7dc7c1f63d3b664b809245680faeef43d8..a6d9dd4a65b38715a6466104ac652b4fc78596b5 100644
--- a/base/build_time_unittest.cc
+++ b/base/build_time_unittest.cc
@@ -7,11 +7,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 TEST(BuildTime, DateLooksValid) {
-#if !defined(DONT_EMBED_BUILD_METADATA)
   char build_date[] = __DATE__;

[agl, 2016/01/29 21:46:46]

I'm not sure when DONT_EMBED_BUILD_METADATA was defined but this test could fail
for people when building with components. But if they weren't building with that
define before then it'll be no worse. Possibly nothing to be done here.

[M-A Ruel, 2016/01/30 02:58:14]

It's meant to be used on the try server.

We want to have no dependence on the build time when building on the try server,
so results can be reused. This is significant, we're talking of almost 50% of
tests skipped due to this on linux.

On the other hand, I'm wiling to take a performance hit to reduce the
configuration knobs.

Similar to what was proposed earlier over email:
- Official build is precise to the resolution of +/-1 day + time zone.
- Non official build is precise at [0~-30]day + time zone.

This way, "chromium" builds would still have some security features enabled but
for shorter.

30 would have to be less than half of the number of days after a build where the
internal table is considered not valid anymore. If the table is good for 70
days, a -30 day variance we should be just fine. I'm purely talking about
non-official build here, for try server, commit queue and continuous integration
testing.

[Zachary Forman, 2016/02/01 07:28:30]

This sounds pretty reasonable to me. I've implemented this with a python script,
so we get 'real' GMT times.

-#else
-  char build_date[] = "Sep 02 2008";
-#endif
 
   EXPECT_EQ(11u, strlen(build_date));
   EXPECT_EQ(' ', build_date[3]);
@@ -19,11 +15,7 @@ TEST(BuildTime, DateLooksValid) {
 }
 
 TEST(BuildTime, TimeLooksValid) {
-#if defined(DONT_EMBED_BUILD_METADATA)
-  char build_time[] = "08:00:00";
-#else
-  char build_time[] = __TIME__;
-#endif
+  char build_time[] = "00:00:00";
 
   EXPECT_EQ(8u, strlen(build_time));
   EXPECT_EQ(':', build_time[2]);