Enhancing the json reader, adding corresponding test case for it

gson/src/main/java/com/google/gson/stream/JsonReader.java

@@ -1561,8 +1561,11 @@ public class JsonReader implements Closeable {
     case '\'':
     case '"':
     case '\\':
+    case '/':	
+    	return escaped;
     default:
-      return escaped;
+    	// throw error when none of the above cases are matched
+    	throw syntaxError("Invalid escape sequence");
     }
   }
 

gson/src/test/java/com/google/gson/stream/JsonReaderTest.java

@@ -174,6 +174,21 @@ public final class JsonReaderTest extends TestCase {
     assertEquals(JsonToken.END_DOCUMENT, reader.peek());
   }
 
+  public void testInvalidJsonInput() throws IOException {
+    String json = "{\n"
+        + "   \"h\\ello\": true,\n"
+        + "   \"foo\": [\"world\"]\n"
+        + "}";
+
+    JsonReader reader = new JsonReader(reader(json));
+    reader.beginObject();
+    try {
+      reader.nextName();
+      fail();
+    } catch (IOException expected) {
+    }
+  }
+  
   public void testNulls() {
     try {
       new JsonReader(null);