Differential updates for components.

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index e757578454bad4cd015d12781080d826b24e1626..8a1fa39c2c6f8a82ac2499729b5bebdbffd051e4 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -514,6 +514,15 @@ const char kEnableCloudPrintProxy[]         = "enable-cloud-print-proxy";
 // supports policy for extensions on Chrome OS.
 const char kEnableComponentCloudPolicy[]    = "enable-component-cloud-policy";
 
+// Enables differential updates for Chrome components, provided that the update
+// server can provide them. Only valid on the browser process.
+const char kEnableComponentUpdateDeltas[]   = "enable-component-update-deltas";
+
+// Enables "pings", requests sent to the update server that report the success
+// or failure of component installation attempts. Only valid on the browser
+// process.
+const char kEnableComponentUpdatePings[]    = "enable-component-update-pings";
+
 // Enables fetching the user's contacts from Google and showing them in the
 // Chrome OS apps list.
 const char kEnableContacts[]                = "enable-contacts";