[Predator] Add clusterfuzz callstack filters.

appengine/findit/crash/stacktrace.py

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 from collections import namedtuple
 import copy
 import logging
 import re
 
 from crash import parse_util
@@ skipping 10 matching lines @@
         r'(.*?):(\d+)(:\d+)?$')
 }
 
 FRAME_INDEX_PATTERN = re.compile(r'\s*#(\d+)\s.*')
 
 _DEFAULT_FORMAT_TYPE = CallStackFormatType.DEFAULT
 
 
 class StackFrame(namedtuple('StackFrame',
     ['index', 'dep_path', 'function', 'file_path', 'raw_file_path',
-    'crashed_line_numbers', 'repo_url'])):
+     'crashed_line_numbers', 'repo_url'])):
   """Represents a frame in a stacktrace.
 
   Attributes:
     index (int): Index shown in the stacktrace if a stackframe line looks like
       this - '#0 ...', else use the index in the callstack list.
     dep_path (str): Path of the dep this frame represents, for example,
       'src/', 'src/v8', 'src/skia'...etc.
     function (str): Function that caused the crash.
     file_path (str): Normalized path of the crashed file, with parts dep_path
       and parts before it stripped, for example, api.cc.
@@ skipping 323 matching lines @@
                   for stack_buffer in self.stacks]
 
     if crash_stack_index is None:
       # If there is no signature callstack, fall back to set crash stack using
       # the first least priority callstack.
       crash_stack = min(callstacks, key=lambda stack: stack.priority)
     else:
       crash_stack = callstacks[crash_stack_index]
 
     return Stacktrace(tuple(callstacks), crash_stack)