platform2: drop libchrome-180609 dependency

libchrome-180609 is deprecated and all platform2 targets are now based
on libchrome-242728.

BUG=chromium:361748
TEST=Trybot runs on paladin, release and chromiumos-sdk builders.

Change-Id: I9afc97baebb241b9567a7e904809d237a2cc3767
Reviewed-on: https://chromium-review.googlesource.com/195570
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
Commit-Queue: Ben Chan <benchan@chromium.org>
diff --git a/common-mk/platform.gyp b/common-mk/platform.gyp
index d9c9954..75aa7d6 100644
--- a/common-mk/platform.gyp
+++ b/common-mk/platform.gyp
@@ -6,9 +6,7 @@
       'target_name': 'All',
       'type': 'none',
       'dependencies': [
-        '<(DEPTH)/platform/libchromeos/libchromeos-180609.gyp:*',
         '<(DEPTH)/platform/libchromeos/libchromeos-242728.gyp:*',
-        '<(DEPTH)/platform/metrics/libmetrics-180609.gyp:*',
         '<(DEPTH)/platform/metrics/libmetrics-242728.gyp:*',
         '<(DEPTH)/platform/metrics/metrics.gyp:*',
         '<(DEPTH)/platform/power_manager/power_manager.gyp:*',