Enable side-by-side beta and dev channels.

chrome/common/chrome_icon_resources_win.h

Index: chrome/common/chrome_icon_resources_win.h
diff --git a/chrome/common/chrome_icon_resources_win.h b/chrome/common/chrome_icon_resources_win.h
index dc18f5a149151709ad4309498d653c77f6a4875d..9400c0b27aebdd00ee9778f7041b6b5d41b0ed5f 100644
--- a/chrome/common/chrome_icon_resources_win.h
+++ b/chrome/common/chrome_icon_resources_win.h
@@ -30,6 +30,12 @@ enum {
 
   // The Chrome incognito icon.
   kIncognitoIndex = 7,
+
+  // The Chrome Dev application icon.
+  kDevApplicationIndex = 8,
+
+  // The Chrome Beta application icon.
+  kBetaApplicationIndex = 9,

[robertshield, 2017/04/05 21:29:37]

part of me want to re-use the legacy indices which iirc were actually never
used. This is fine too though.

[grt (UTC plus 2), 2017/04/20 13:53:04]

huh. i can't find any record of them being used, either (they were added for
https://crbug.com/12701). i seem to recall there being a teeny tiny trickle of
complaints when the placeholders landed, so i think it's safest to not reuse
them.

 #else   // defined(GOOGLE_CHROME_BUILD)
   // The Chromium App Launcher icon.
   kAppLauncherIndex = 1,