Revert "Update third_party/checkstyle to 7.6.1"

This reverts commit dbce02f6.

Reason for revert:
Breaking cq presubmit step

Original issue's description:
> Update third_party/checkstyle to 7.6.1
>
> This CL updates third_party/checkstyle to 7.6.1 so checkstyle would
> work with Java 8 lambda features.
>
> BUG=703238
>
> Review-Url: https://codereview.chromium.org/2799303003
> Cr-Commit-Position: refs/heads/master@{#462968}
> Committed: https://chromium.googlesource.com/chromium/src/+/dbce02f63421f7d446d6ef317b456f6ae911f63b

TBR=agrieve@chromium.org,nyquist@chromium.org,jbudorick@chromium.org,klobag@chromium.org,jbudorick@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=703238

Review-Url: https://codereview.chromium.org/2807753003 .
Cr-Commit-Position: refs/heads/master@{#463021}

DEPS

@@ -720,16 +720,6 @@ hooks = [
                '-l', 'third_party/retrolambda'
     ],
   },
-  {
-    'name': 'checkstyle',
-    'pattern': '.',
-    'action': ['python',
-               'src/build/android/update_deps/update_third_party_deps.py',
-               'download',
-               '-b', 'chromium-android-tools/checkstyle',
-               '-l', 'third_party/checkstyle'
-    ],
-  },
   {
     'name': 'apk-patch-size-estimator',
     'pattern': '.',

third_party/.gitignore

@@ -32,7 +32,6 @@
 /cardboard-java/src
 /catapult
 /ced/src
-/checkstyle/*.jar
 /chromeos_login_manager
 /chromeos_text_input
 /chromite

third_party/checkstyle/OWNERS

-agrieve@chromium.org
-jbudorick@chromium.org
-nyquist@chromium.org
-zpeng@chromium.org
-
+aurimas@chromium.org

third_party/checkstyle/README.chromium

 Name: Checkstyle is a development tool to help programmers write Java code that
       adheres to a coding standard.
 Short Name: checkstyle
-URL: https://github.com/checkstyle/checkstyle
-Version: 7.6.1
+URL: http://checkstyle.sourceforge.net/
+Version: 6.5
 License: LGPL 2.1
 License File: NOT_SHIPPED
 Security Critical: no
@@ -11,15 +11,5 @@ Description:
 Checkstyle is used to validate Java code style on Chromium PRESUBMIT step.
 
 Local Modifications:
-None
-
-Update instructions (requires @google.com account):
-- Download fat jar from https://sourceforge.net/projects/checkstyle/files/checkstyle/
-- Modify tools/android/checkstyle/checkstyle.py and verify the new fat jar works
-- Remove existing SHA1 file
-- If gcloud auth tokens are not set up, run
-$ download_from_google_storage --config
-- Upload new fat jar to gcloud. In third_party/checkstyle, run
-$ upload_to_google_storage.py -b chromium-android-tools/checkstyle {new_far_jar}
-- Check in new SHA1 file
-
+- Downloaded checkstyle-6.5-all.jar without source code development
+  documentation.

third_party/checkstyle/checkstyle-7.6.1-all.jar.sha1

-c6889fa07ec9afb0ca8029be75de31dc29dc4f05
\ No newline at end of file

tools/android/checkstyle/checkstyle.py

@@ -13,15 +13,7 @@ CHROMIUM_SRC = os.path.normpath(
     os.path.join(os.path.dirname(__file__),
                  os.pardir, os.pardir, os.pardir))
 CHECKSTYLE_ROOT = os.path.join(CHROMIUM_SRC, 'third_party', 'checkstyle',
-                               'checkstyle-7.6.1-all.jar')
-
-
-def FormatCheckstyleOutput(checkstyle_output):
-  lines = checkstyle_output.splitlines(True)
-  if 'Checkstyle ends with' in lines[-1]:
-    return ''.join(lines[:-1])
-  else:
-    return checkstyle_output
+                               'checkstyle-6.5-all.jar')
 
 
 def RunCheckstyle(input_api, output_api, style_file, black_list=None):
@@ -57,10 +49,8 @@ def RunCheckstyle(input_api, output_api, style_file, black_list=None):
   result_errors = []
   result_warnings = []
 
-  formatted_checkstyle_output = FormatCheckstyleOutput(stdout)
-
   local_path = input_api.PresubmitLocalPath()
-  root = xml.dom.minidom.parseString(formatted_checkstyle_output)
+  root = xml.dom.minidom.parseString(stdout)
   for fileElement in root.getElementsByTagName('file'):
     fileName = fileElement.attributes['name'].value
     fileName = os.path.relpath(fileName, local_path)