added unittest to check for unmodifiable storage corner case on dict init

- fixed style

Author: cosminbasca

graalpython/com.oracle.graal.python.test/src/tests/test_dict.py

@@ -285,3 +285,7 @@ def test_create_seq_and_kw():
     d = dict({'a': 1, 'b': 2, 'c': 3}, d=4)
     for k in ['a', 'b', 'c', 'd']:
         assert k in d
+
+    d = dict(dict(a=1, b=2, c=3), d=4)
+    for k in ['a', 'b', 'c', 'd']:
+        assert k in d

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/common/HashingStorageNodes.java

@@ -302,7 +302,7 @@ public void doPDict(PDict self, PDict iterable, @SuppressWarnings("unused") PKey
 
         @Specialization(guards = {"!isNoValue(iterable)", "!isEmpty(kwargs)"}, rewriteOn = HashingStorage.UnmodifiableStorageException.class)
         public void doPDictKwargs(PDict self, PDict iterable, PKeyword[] kwargs,
-                                  @Cached("create()") UnionNode unionNode) {
+                        @Cached("create()") UnionNode unionNode) {
             HashingStorage dictStorage = unionNode.execute(iterable.getDictStorage(), new KeywordsStorage(kwargs));
             self.setDictStorage(dictStorage);
         }