Add metrics for user manually added exceptions

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index b533a7f080b3605522396036a7db2dd580fe82a6..48fa8080db294758b2c3d1960347b7de6dbfc9e8 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -5634,6 +5634,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="ContentSettings.AddManualException" enum="ContentType">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    Number of times a manually input exception for a given content setting type
+    was added.
+  </summary>
+</histogram>
+
 <histogram name="ContentSettings.DefaultCookiesSetting" enum="ContentSetting">
   <owner>toyoshim@chromium.org</owner>
   <summary>The default cookies setting at profile open.</summary>
@@ -5762,6 +5770,111 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="ContentSettings.NumberOfAllowAutomaticDownloadsExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined automatic downloads exceptions for allowing
+    automatic downloads at browser start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfAllowImagesExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined images exceptions for allowing images at browser
+    start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfAllowJavaScriptExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined JavaScript exceptions for allowing JavaScript at
+    browser start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfAllowPluginsExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined plugin exceptions for allowing plugins at browser
+    start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfAllowPopupsExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined popup exceptions for allowing popups at browser
+    start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfAskAutomaticDownloadsExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined automatic downloads exceptions for asking
+    automatic downloads at browser start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfAskPluginsExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined plugin exceptions for asking plugins at browser
+    start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfBlockAutomaticDownloadsExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined automatic downloads exceptions for blocking
+    automatic downloads at browser start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfBlockImagesExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined images exceptions for blocking images at browser
+    start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfBlockJavaScriptExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined JavaScript exceptions for blocking JavaScript at
+    browser start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfBlockPluginsExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined plugin exceptions for blocking plugins at browser
+    start.
+  </summary>
+</histogram>
+
+<histogram name="ContentSettings.NumberOfBlockPopupsExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined popup exceptions for blocking popups at browser
+    start.
+  </summary>
+</histogram>
+
+<histogram
+    name="ContentSettings.NumberOfDetectImportantContentPluginsExceptions">
+  <owner>lshang@chromium.org</owner>
+  <summary>
+    The number of user defined plugin exceptions for detecting important content
+    plugins at browser start.
+  </summary>
+</histogram>
+
 <histogram name="ContentSettings.PermissionActions" enum="PermissionAction">
   <obsolete>
     Removed 11/2015 in favor of Permissions.Action.*