histograms: Add ESWMF_INVALID_DECREMENT_ACTIVITY bad message reason

Generated by tools/metrics/histograms/update_bad_message_reasons.py
This reason was added in https://crrev.com/4c82177a8b45303c941ddbc469444f0bfc760de4
Also fix typo.

BUG=602442

Review-Url: https://chromiumcodereview.appspot.com/2429283004
Cr-Commit-Position: refs/heads/master@{#426554}

extensions/browser/bad_message.h

@@ -30,7 +30,7 @@ enum BadMessageReason {
   AVG_BAD_EXT_ID = 5,
   AVG_NULL_AVG = 6,
   // Invalid decrement of an Extensions SW ref count.
-  ESWMF_INVALID_DECREMENT_ACTIVIY = 7,
+  ESWMF_INVALID_DECREMENT_ACTIVITY = 7,
   // Please add new elements here. The naming convention is abbreviated class
   // name (e.g. ExtensionHost becomes EH) plus a unique description of the
   // reason. After making changes, you MUST update histograms.xml by running:

extensions/browser/extension_service_worker_message_filter.cc

@@ -71,7 +71,7 @@ void ExtensionServiceWorkerMessageFilter::OnDecrementServiceWorkerActivity(
       service_worker_version_id, request_uuid);
   if (!status) {
     bad_message::ReceivedBadMessage(
-        this, bad_message::ESWMF_INVALID_DECREMENT_ACTIVIY);
+        this, bad_message::ESWMF_INVALID_DECREMENT_ACTIVITY);
   }
 }
 

tools/metrics/histograms/histograms.xml

@@ -73861,6 +73861,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="4" label="AVG_BAD_INST_ID"/>
   <int value="5" label="AVG_BAD_EXT_ID"/>
   <int value="6" label="AVG_NULL_AVG"/>
+  <int value="7" label="ESWMF_INVALID_DECREMENT_ACTIVITY"/>
 </enum>
 
 <enum name="BadMessageReasonNaCl" type="int">