Introduce chrome.displaySource API

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 a9bcacabb75ad029f31b401e6e5735bfdf9e0cab..76f4574ce6ee52bab23385c3d80229307da85345 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -58315,6 +58315,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="389" label="EASY_UNLOCK_PRIVATE_ON_CONNECTION_STATUS_CHANGED"/>
   <int value="390" label="EASY_UNLOCK_PRIVATE_ON_DATA_RECEIVED"/>
   <int value="391" label="EASY_UNLOCK_PRIVATE_ON_SEND_COMPLETED"/>
+  <int value="392" label="DISPLAY_SOURCE_ON_SINKS_UPDATED"/>
 </enum>
 
 <enum name="ExtensionFileWriteResult" type="int">
@@ -59454,6 +59455,8 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="1091" label="TABCAPTURE_CAPTUREOFFSCREENTAB"/>
   <int value="1092" label="LANGUAGESETTINGSPRIVATE_ADDSPELLCHECKWORD"/>
   <int value="1093" label="LANGUAGESETTINGSPRIVATE_REMOVESPELLCHECKWORD"/>
+  <int value="1094" label="DISPLAYSOURCE_GETAVAILABLESINKS"/>
+  <int value="1095" label="DISPLAYSOURCE_REQUESTAUTHENTICATION"/>
 </enum>
 
 <enum name="ExtensionInstallCause" type="int">