Add extensions code to use common updater in components/update_client/

This is another piece of work towards implementing differential
extensions update and share autoupdate code with the chrome components
system. It adds code to the extensions/browser directory that makes use
of the common autoupdate code via the update_client::UpdateClient class
to send update checks to the server, download a full .crx or
differential update, and hand back an unpacked directory with the
contents of the new extension version.

This CL does not yet add any code in chrome/ that actually uses these
new capabilities; that will be in a forthcoming CL.

BUG=490418

Review URL: https://codereview.chromium.org/1362043005

Cr-Commit-Position: refs/heads/master@{#354370}

2 files changed, 0 insertions, 4 deletions

diff --git a/extensions/shell/common/switches.cc b/extensions/shell/common/switches.cc
index fbb5783..66bd7e5 100644
--- a/extensions/shell/common/switches.cc
+++ b/extensions/shell/common/switches.cc
@@ -13,9 +13,6 @@ const char kAppShellAllowRoaming[] = "app-shell-allow-roaming";
 // Size for the host window to create (i.e. "800x600").
 const char kAppShellHostWindowSize[] = "app-shell-host-window-size";
 
-// ID of an extension CRX to be downloaded from the web store.
-const char kAppShellInstallCrx[] = "app-shell-install-crx";
-
 // SSID of the preferred WiFi network.
 const char kAppShellPreferredNetwork[] = "app-shell-preferred-network";
 
diff --git a/extensions/shell/common/switches.h b/extensions/shell/common/switches.h
index b6b3932..7cfe1d6 100644
--- a/extensions/shell/common/switches.h
+++ b/extensions/shell/common/switches.h
@@ -12,7 +12,6 @@ namespace switches {
 // alongside the definition of their values in the .cc file.
 extern const char kAppShellAllowRoaming[];
 extern const char kAppShellHostWindowSize[];
-extern const char kAppShellInstallCrx[];
 extern const char kAppShellPreferredNetwork[];
 extern const char kAppShellRefreshToken[];
 extern const char kAppShellUser[];