DNS Host resolver changes with retry logic. Fix for

bug Chromium cannot recover from a state when its 
DNS requests have been dropped.

Whenever we try to resolve the host, we post a delayed task
to check if host resolution (OnLookupComplete) is completed 
or not. If the original ateempt hasn't completed, then we start
another attempt to resolve for the same request.

We take the results from the attempt that finishes first and
leave all other attempts as orphaned.

BUG=73327
TEST=dns host resolver tests
R=eroman,jar
Review URL: http://codereview.chromium.org/6782001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@83641 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 22 insertions, 0 deletions

diff --git a/base/metrics/histogram_unittest.cc b/base/metrics/histogram_unittest.cc
index 496ff63..9d671df 100644
--- a/base/metrics/histogram_unittest.cc
+++ b/base/metrics/histogram_unittest.cc
@@ -288,6 +288,28 @@ TEST(HistogramTest, BoundsTest) {
   EXPECT_EQ(kBucketCount, array_size);
   EXPECT_EQ(0, sample.counts(array_size - 2));
   EXPECT_EQ(2, sample.counts(array_size - 1));
+
+  std::vector<int> custom_ranges;
+  custom_ranges.push_back(10);
+  custom_ranges.push_back(50);
+  custom_ranges.push_back(100);
+  Histogram* test_custom_histogram(CustomHistogram::FactoryGet(
+      "TestCustomRangeBoundedHistogram", custom_ranges, Histogram::kNoFlags));
+
+  // Put two samples "out of bounds" above and below.
+  test_custom_histogram->Add(5);
+  test_custom_histogram->Add(-50);
+  test_custom_histogram->Add(100);
+  test_custom_histogram->Add(1000);
+
+  // Verify they landed in the underflow, and overflow buckets.
+  Histogram::SampleSet custom_sample;
+  test_custom_histogram->SnapshotSample(&custom_sample);
+  EXPECT_EQ(2, custom_sample.counts(0));
+  EXPECT_EQ(0, custom_sample.counts(1));
+  size_t custom_array_size = test_custom_histogram->bucket_count();
+  EXPECT_EQ(0, custom_sample.counts(custom_array_size - 2));
+  EXPECT_EQ(2, custom_sample.counts(custom_array_size - 1));
 }
 
 // Check to be sure samples land as expected is "correct" buckets.