Re-land http://codereview.chromium.org/6869009 (except for the suppressions)

Introduce the ANNOTATE_LEAKING_OBJECT_PTR annotation that can be used to mark
heap allocated objects as intentionally leaked ones.
Annotate the histograms produced by {Histogram,BooleanHistogram,LinearHistogram,CustomHistogram}::FactoryGet(), as leaked.

Rename StatsHistogram::StatsHistogramFactoryGet to StatsHistogram::FactoryGet, annotate the result as leaky.

The previous commit broke the build on Linux Heapcheck, but looks like the problem has gone now.

TBR=jar,willchan
BUG=79322
Review URL: http://codereview.chromium.org/7048005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@85898 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 5 insertions, 4 deletions

diff --git a/net/disk_cache/stats.cc b/net/disk_cache/stats.cc
index 6fdd31c..af3b941 100644
--- a/net/disk_cache/stats.cc
+++ b/net/disk_cache/stats.cc
@@ -151,7 +151,7 @@ bool Stats::Init(BackendImpl* backend, uint32* storage_addr) {
       // Stats may be reused when the cache is re-created, but we want only one
       // histogram at any given time.
       size_histogram_ =
-          StatsHistogram::StatsHistogramFactoryGet("DiskCache.SizeStats");
+          StatsHistogram::FactoryGet("DiskCache.SizeStats");
       size_histogram_->Init(this);
     }
   }
diff --git a/net/disk_cache/stats_histogram.cc b/net/disk_cache/stats_histogram.cc
index 6d3097a..14d2d70 100644
--- a/net/disk_cache/stats_histogram.cc
+++ b/net/disk_cache/stats_histogram.cc
@@ -4,6 +4,7 @@
 
 #include "net/disk_cache/stats_histogram.h"
 
+#include "base/debug/leak_annotations.h"
 #include "base/logging.h"
 #include "net/disk_cache/stats.h"
 
@@ -21,8 +22,7 @@ StatsHistogram::~StatsHistogram() {
     stats_ = NULL;
 }
 
-StatsHistogram* StatsHistogram::StatsHistogramFactoryGet(
-    const std::string& name) {
+StatsHistogram* StatsHistogram::FactoryGet(const std::string& name) {
   Histogram* histogram(NULL);
 
   Sample minimum = 1;
@@ -49,6 +49,7 @@ StatsHistogram* StatsHistogram::StatsHistogramFactoryGet(
   // Validate upcast by seeing that we're probably providing the checksum.
   CHECK_EQ(return_histogram->StatsHistogram::CalculateRangeChecksum(),
            return_histogram->CalculateRangeChecksum());
+  ANNOTATE_LEAKING_OBJECT_PTR(return_histogram); // see crbug.com/79322
   return return_histogram;
 }
 
diff --git a/net/disk_cache/stats_histogram.h b/net/disk_cache/stats_histogram.h
index 83d359c..627286bf 100644
--- a/net/disk_cache/stats_histogram.h
+++ b/net/disk_cache/stats_histogram.h
@@ -35,7 +35,7 @@ class StatsHistogram : public base::Histogram {
       : Histogram(name, minimum, maximum, bucket_count), init_(false) {}
   ~StatsHistogram();
 
-  static StatsHistogram* StatsHistogramFactoryGet(const std::string& name);
+  static StatsHistogram* FactoryGet(const std::string& name);
 
   // We'll be reporting data from the given set of cache stats.
   bool Init(const Stats* stats);