Implement Web Restrictions in WebView.

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 ac91167b744d32bd94dfd9e71de54ae2313017cb..fc24dab417326f3e0abcc48e43d31e9195fab01c 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -66329,7 +66329,8 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="14" label="Enable Safe Browsing"/>
   <int value="15" label="Enable reporting of usage and crash-related data"/>
   <int value="16" label="Enable saving passwords to the password manager"/>
-  <int value="17" label="Allow users to show passwords in Password Manager"/>
+  <int value="17"
+      label="Allow users to show passwords in Password Manager (deprecated)"/>
   <int value="18" label="Enable AutoFill"/>
   <int value="19" label="Specify a list of disabled plugins"/>
   <int value="20" label="Disable synchronization of data with Google"/>
@@ -66722,18 +66723,20 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="315" label="Block key generation on these sites"/>
   <int value="316"
       label="Configure the required domain name for remote access clients"/>
-  <int value="317" label="ARC Enabled"/>
+  <int value="317" label="Enable ARC"/>
   <int value="318" label="Configure ARC apps"/>
   <int value="319"
       label="Allow the auto launched with zero delay kiosk app to control
-             ChromeOS version"/>
+             Google Chrome OS version"/>
   <int value="320" label="Control use of the Web Bluetooth API"/>
   <int value="321" label="Configure the login authentication behavior"/>
   <int value="322" label="Whitelist of USB detachable devices"/>
   <int value="323" label="Allow bluetooth on device"/>
   <int value="324" label="Suppress the unsupported OS warning"/>
-  <int value="325" label="Enable queries to Quirks Server"/>
+  <int value="325"
+      label="Enable queries to Quirks Server for hardware profiles"/>
   <int value="326" label="Configure the automatic timezone detection method"/>
+  <int value="327" label="Set an external source of URL restrictions"/>
 </enum>
 
 <enum name="EnterprisePolicyInvalidations" type="int">