fix($location): always decode special chars in $location.url(value)

The original fix for #16312 included changing how `$location.url(value)`
decoded the special characters passed to it as a setter.
This broke a number of use cases (mostly involving the ui-router).

Further analysis appears to show that we can solve #16312, to prevent
urls being rewritten with decoded values, without modifying the
behaviour of `$location.url`.

This commit reverts changes to `$location.url(value)` so that encoded
chars will once again be decoded and passed to `$location.path(value)`.
In particular it will convert encoded forward slashes, which changes how
the path is updated, since e.g. `a/b/%2Fc%2Fd` will become `a/b/c/d`.
While this is arguably not "correct", it appears that there are too many
use cases relying upon this behaviour.

src/ng/location.js

@@ -422,7 +422,7 @@ var locationPrototype = {
     }
 
     var match = PATH_MATCH.exec(url);
-    if (match[1] || url === '') this.path((this.$$html5 ? decodeURI : decodeURIComponent)(match[1]));
+    if (match[1] || url === '') this.path(decodeURIComponent(match[1]));
     if (match[2] || match[1] || url === '') this.search(match[3] || '');
     this.hash(match[5] || '');
 

test/ng/locationSpec.js

@@ -681,11 +681,11 @@ describe('$location', function() {
         expect(locationUrl.path()).toEqual('/foo:bar');
       });
 
-      it('url() should not decode non-component special characters in html5 mode', function() {
+      it('url() should decode non-component special characters in html5 mode', function() {
         var locationUrl = new LocationHtml5Url('http://host.com', 'http://host.com');
         locationUrl.$$parse('http://host.com');
         locationUrl.url('/foo%3Abar');
-        expect(locationUrl.path()).toEqual('/foo%3Abar');
+        expect(locationUrl.path()).toEqual('/foo:bar');
       });
     });
   });