Created skeleton for switch access component extension.

chrome/common/extensions/extension_constants.cc

Index: chrome/common/extensions/extension_constants.cc
diff --git a/chrome/common/extensions/extension_constants.cc b/chrome/common/extensions/extension_constants.cc
index c559508b41c2e67f8ca431745e9e95dab6ee25de..5923f7efc6c671cde7ff6741fa145c8cc7eeda49 100644
--- a/chrome/common/extensions/extension_constants.cc
+++ b/chrome/common/extensions/extension_constants.cc
@@ -63,6 +63,8 @@ const char kChromeVoxExtensionId[] = "mndnfokpggljbaajbnioimlmbfngpief";
 const char kChromeVoxExtensionPath[] = "chromeos/chromevox";
 const char kSelectToSpeakExtensionId[] = "klbcgckkldhdhonijdbnhhaiedfkllef";
 const char kSelectToSpeakExtensionPath[] = "chromeos/select_to_speak";
+const char kSwitchAccessExtensionId[] = "pmehocpgjmkenlokgjfkaichfjdhpeol";
+const char kSwitchAccessExtensionPath[] = "chromeos/switch_access";
 const char kGuestManifestFilename[] = "manifest_guest.json";
 const char kBrailleImeExtensionId[] =
     "jddehjeebkoimngcbdkaahpobgicbffp";