Add a histogram for the number of hostname patterns for content settings

chrome/browser/content_settings/content_settings_pref_provider.cc

Index: chrome/browser/content_settings/content_settings_pref_provider.cc
diff --git a/chrome/browser/content_settings/content_settings_pref_provider.cc b/chrome/browser/content_settings/content_settings_pref_provider.cc
index 0d26a262621813aaa3044506a6763415870d6837..feb5c1cbd1486c2d6ad6018acdd46240b20cda2e 100644
--- a/chrome/browser/content_settings/content_settings_pref_provider.cc
+++ b/chrome/browser/content_settings/content_settings_pref_provider.cc
@@ -9,6 +9,7 @@
 #include <vector>
 
 #include "base/command_line.h"
+#include "base/metrics/histogram.h"
 #include "chrome/browser/content_settings/content_settings_details.h"
 #include "chrome/browser/content_settings/content_settings_pattern.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ -372,6 +373,11 @@ void PrefProvider::Init() {
   // Read exceptions.
   ReadExceptions(false);
 
+  if (!is_incognito()) {
+    UMA_HISTOGRAM_COUNTS("ContentSettings.NumberOfExceptions",

[jar (doing other things), 2011/05/25 02:19:50]

One thing to test is to be sure the histogram system is initialized before you
record this data. 

To test: Start up the browser, and then visit:
about:histograms/ContentSettings.NumberOfExceptions

IF you see data, then everything is fine.  If you don't, then we'll need to work
a bit harder.  The histogram system is initialized pretty early.... but you
should check.

+                         host_content_settings()->size());
+  }
+
   pref_change_registrar_.Init(prefs);
   pref_change_registrar_.Add(prefs::kContentSettingsPatterns, this);