Revert of Add PRESUBMIT check if modified UMA histogram name can be found (patchset #2 id:40001 of https://codereview.chromium.org/766713004/)

Reason for revert:
Produces false positive warnings on histograms using histogram_suffixes, see:

https://code.google.com/p/chromium/issues/detail?id=445265

Original issue's description:
> Add PRESUBMIT check if modified UMA histogram name can be found
>
> This Presubmit checks if some diffs affect any UMA_HISTOGRAM_*
> macro and, if so, checks if the histogram name is to be found
> in either tools/metrics/histograms/histograms.xml or in the
> CL diffs.
>
> Addresses the problem of someone modifying code and
> inadvertently forgetting a corresponding histograms.xml
> adaptation, that has happened in the past.
>
> BUG=434420
>
> Committed: https://crrev.com/2ece5270462346b1ac3bccd3bfe5e68d024b98b5
> Cr-Commit-Position: refs/heads/master@{#306388}

TBR=phajdan.jr@chromium.org,mcasas@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=434420, 445265

Review URL: https://codereview.chromium.org/841323002

Cr-Commit-Position: refs/heads/master@{#310863}

1 files changed, 0 insertions, 22 deletions

diff --git a/PRESUBMIT_test.py b/PRESUBMIT_test.py
index 9d82644..6daae16 100755
--- a/PRESUBMIT_test.py
+++ b/PRESUBMIT_test.py
@@ -270,28 +270,6 @@ class VersionControlConflictsTest(unittest.TestCase):
     self.assertTrue('3' in errors[1])
     self.assertTrue('5' in errors[2])
 
-class UmaHistogramChangeMatchedOrNotTest(unittest.TestCase):
-  def testTypicalNotMatchedChange(self):
-    diff = ['UMA_HISTOGRAM_BOOL("Bla.Foo.Dummy", true)']
-    mock_input_api = MockInputApi()
-    mock_input_api.files = [MockFile('some/path/foo.cc', diff)]
-    warnings = PRESUBMIT._CheckUmaHistogramChanges(mock_input_api,
-                                                   MockOutputApi())
-    self.assertEqual(1, len(warnings))
-    self.assertEqual('warning', warnings[0].type)
-
-  def testTypicalCorrectlyMatchedChange(self):
-    diff_cc = ['UMA_HISTOGRAM_BOOL("Bla.Foo.Dummy", true)']
-    diff_xml = ['<histogram name="Bla.Foo.Dummy"> </histogram>']
-    mock_input_api = MockInputApi()
-    mock_input_api.files = [
-      MockFile('some/path/foo.cc', diff_cc),
-      MockFile('tools/metrics/histograms/histograms.xml', diff_xml),
-    ]
-    warnings = []
-    warnings = PRESUBMIT._CheckUmaHistogramChanges(mock_input_api,
-                                                   MockOutputApi())
-    self.assertEqual(0, len(warnings))
 
 class BadExtensionsTest(unittest.TestCase):
   def testBadRejFile(self):