Move histogram_manager from components/metrics to components/cronet

components/cronet/histogram_manager_unittest.cc

Index: components/cronet/histogram_manager_unittest.cc
diff --git a/components/metrics/histogram_manager_unittest.cc b/components/cronet/histogram_manager_unittest.cc
similarity index 92%
rename from components/metrics/histogram_manager_unittest.cc
rename to components/cronet/histogram_manager_unittest.cc
index 5e5f99261b9dbcbcfc8d6cd660d8de3909fb78c4..bb0eff892b82572534b97abf59764ffdca2502d1 100644
--- a/components/metrics/histogram_manager_unittest.cc
+++ b/components/cronet/histogram_manager_unittest.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "components/metrics/histogram_manager.h"
+#include "components/cronet/histogram_manager.h"
 
 #include <string>
 
@@ -11,8 +11,6 @@
 
 namespace metrics {
 
-// TODO(mef): crbug.com/441441. Move components/metrics/histogram_manager.*
-// files into components/android/cronet.
 // TODO(rtenneti): enable flaky HistogramBucketFields unit test.
 TEST(HistogramManager, DISABLED_HistogramBucketFields) {

[Alexei Svitkine (slow), 2015/04/08 17:56:37]

Any idea why this is still disabled/flaky? Are you planning to take a look at
that after this?

Otherwise, this test wouldn't actually be running.

[mef, 2015/04/08 18:06:04]

Good question, I probably should, although I'm not sure how to test this. 
I could drop this unittest and test through java instrumentation, but I suppose
that we may want to use HistogramManager in Cronet on iOS in foreseeable future.
Raman, do you remember, what was causing test flakiness?

[ramant (doing other things), 2015/04/08 18:22:13]

I don't remember. Is it possible try LOCAL_HISTOGRAM_ENUMERATION and see if it
works or not. The difference between this UMA_... whether the histogram is used
for upload or not.

   // Capture histograms at the start of the test to avoid later GetDeltas()