Revert the debugging changes that added vm abort flag and core dumps.

tools/bots/bot_utils.py

Index: tools/bots/bot_utils.py
diff --git a/tools/bots/bot_utils.py b/tools/bots/bot_utils.py
index d92f4271f88d13a7fbc0f5b3269fe579ae0b5c6f..1feaf2c136af693a83f85ff4ddff2457d3e39ed9 100644
--- a/tools/bots/bot_utils.py
+++ b/tools/bots/bot_utils.py
@@ -12,13 +12,6 @@ import string
 import subprocess
 import sys
 
-# The resource package does not exist on Windows but its functionality is not
-# used there, either.
-try:
-  import resource
-except ImportError:
-  resource = None;
-
 DART_DIR = os.path.abspath(
     os.path.normpath(os.path.join(__file__, '..', '..', '..')))
 
@@ -372,14 +365,3 @@ def GetChannelFromName(name):
   if channel_name in Channel.ALL_CHANNELS:
     return channel_name
   return Channel.BLEEDING_EDGE
-
-class CoredumpEnabler(object):
-  def __init__(self):
-    self._old_limits = None
-
-  def __enter__(self):
-    self._old_limits = resource.getrlimit(resource.RLIMIT_CORE)
-    resource.setrlimit(resource.RLIMIT_CORE, (-1, -1))
-
-  def __exit__(self, *_):
-    resource.setrlimit(resource.RLIMIT_CORE, self._old_limits)