suppress intentional leak from SampleMap sparse histogram

TBR=bruening@chromium.org
BUG=NONE

Review URL: https://codereview.chromium.org/23620030

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@222059 0039d316-1c4b-4281-b951-d872f2087c98

tools/valgrind/drmemory/suppressions_full.txt

@@ -1024,6 +1024,12 @@ name=deliberate histogram leak
 ...
 *!*::*Histogram::FactoryGet
 
+LEAK
+name=deliberate leak for SampleMap
+...
+*!base::SampleMap::Accumulate
+*!base::SparseHistogram::Add
+
 LEAK
 name=deliberate LazyInstance leak
 ...