Remove libbase_ver override in gyp file.

CL:194476 modified platform2 to build against libchrome-242728. The
libbase_ver override in the gyp file is no longer needed.

BUG=chromium:361748
TEST=`FEATURES=test emerge-$BOARD platform2`
TEST=Verify that cros-disks is linked against libchrome-242728.

Change-Id: I69743dc3142d259a827c3e4d3df7504e4823435e
Reviewed-on: https://chromium-review.googlesource.com/194832
Tested-by: Ben Chan <benchan@chromium.org>
Reviewed-by: Paul Stewart <pstew@chromium.org>
Commit-Queue: Ben Chan <benchan@chromium.org>
diff --git a/cros-disks.gyp b/cros-disks.gyp
index 589d40e..19a1d1f 100644
--- a/cros-disks.gyp
+++ b/cros-disks.gyp
@@ -1,7 +1,4 @@
 {
-  'variables': {
-    'libbase_ver': 242728,
-  },
   'target_defaults': {
     'dependencies': [
       '../libchromeos/libchromeos-<(libbase_ver).gyp:libchromeos-<(libbase_ver)',