[Android] Incorporate findbugs into android builds.

build/java_apk.gypi

Index: build/java_apk.gypi
diff --git a/build/java_apk.gypi b/build/java_apk.gypi
index c5e7ae3f110ad6ccac6b073daeee993aefc0ec3f..56aefdf96778cb66a9c8e0bc5058d297d08131e3 100644
--- a/build/java_apk.gypi
+++ b/build/java_apk.gypi
@@ -103,6 +103,8 @@
     'lint_result': '<(intermediate_dir)/lint_result.xml',
     'lint_config': '<(intermediate_dir)/lint_config.xml',
     'never_lint%': 0,
+    'findbugs_stamp': '<(intermediate_dir)/findbugs.stamp',
+    'run_findbugs%': 0,
     'java_in_dir_suffix%': '/src',
     'instr_stamp': '<(intermediate_dir)/instr.stamp',
     'jar_stamp': '<(intermediate_dir)/jar.stamp',
@@ -558,6 +560,32 @@
         '<(DEPTH)/tools/android/android_tools.gyp:android_tools',
       ]
     }],
+    ['run_findbugs == 1', {
+      'actions': [
+        {
+          'action_name': 'findbugs_<(_target_name)',
+          'message': 'Running findbugs on <(_target_name)',
+          'inputs': [
+            '<(DEPTH)/build/android/findbugs_diff.py',
+            '<(DEPTH)/build/android/findbugs_filter/findbugs_exclude.xml',
+            '<(DEPTH)/build/android/pylib/utils/findbugs.py',
+            '>@(input_jars_paths)',
+            '<(jar_path)',
+            '<(compile_stamp)',
+          ],
+          'outputs': [
+            '<(findbugs_stamp)',
+          ],
+          'action': [
+            'python', '<(DEPTH)/build/android/findbugs_diff.py',
+            '--auxclasspath-gyp', '>(input_jars_paths)',
+            '--stamp', '<(findbugs_stamp)',
+            '<(jar_path)',
+          ],
+        },
+      ],
+    },
+    ]
   ],
   'dependencies': [
     '<(DEPTH)/tools/android/md5sum/md5sum.gyp:md5sum',