Revert of Disable excluding of tested apk's code in test apks...

Revert of Disable excluding of tested apk's code in test apks (https://codereview.chromium.org/331683005/)

Reason for revert:
We are hitting the issue in https://code.google.com/p/chromium/issues/detail?id=272790 again. So we will have to reenable this fix.

The failing tests are being handled in separate CLs I believe.

Original issue's description:
> The new way of building test APKs loses some
> necessary classes from them, hence causing them to fail with
> "Class not found" errors. 
> 
> Disable this until we have a fix.
> 
> BUG=384537,272790
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=277756

TBR=aberent@chromium.org,cjhopman@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=384537,272790

Review URL: https://codereview.chromium.org/341973002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278118 0039d316-1c4b-4281-b951-d872f2087c98

build/java_apk.gypi

@@ -162,7 +162,7 @@
     'conditions': [
       ['proguard_enabled == "true"', {
         'variables': {
-          #'proguard_enabled': 'true',
+          'proguard_enabled': 'true',
         }
       }],
     ],
@@ -713,7 +713,7 @@
         ['is_test_apk == 1 and tested_apk_dex_path != "/"', {
           'variables': {
             'dex_additional_options': [
-              #'--excluded-paths-file', '>(tested_apk_dex_path).inputs'
+              '--excluded-paths-file', '>(tested_apk_dex_path).inputs'
             ],
           },
           'inputs': [