fix(filter): filter on false properties

Code was evaluating !expression[key] while attempting to
see if the key was present, but this was evaluating to true for
false values as well as missing keys.

Closes #2797.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/ng/filter/filter.js b/src/ng/filter/filter.js
index 5c3c917b..be01b1b3 100644
--- a/src/ng/filter/filter.js
+++ b/src/ng/filter/filter.js
@@ -183,7 +183,7 @@ function filterFilter() {
             })();
           } else {
             (function() {
-              if (!expression[key]) return;
+              if (typeof(expression[key]) == 'undefined') { return; }
               var path = key;
               predicates.push(function(value) {
                 return search(getter(value,path), expression[path]);