getters: don't ignore frame selection. closes #208

lib/getters.js

@@ -266,7 +266,7 @@ module.exports = function (gm) {
       args.push('-verbose');
     }
 
-    args.push(self.sourceStream || self.sourceBuffer ? '-' : self.source);
+    args = args.concat(self.src());
     return args;
   }
 

test/gifFrameIdentify.js

@@ -0,0 +1,17 @@
+
+var assert = require('assert')
+var fs = require('fs');
+
+module.exports = function (_, dir, finish, gm) {
+  var m = gm(dir + '/original.gif[0]')
+
+  if (!gm.integration)
+    return finish();
+
+  m.identify('%n', function (err, stdout) {
+    if (err) return finish(err);
+
+    assert.equal(parseInt(stdout.toString(), 10), 1);
+    finish();
+  })
+}