Raise DataError properly from Zlib::Inflate#inflate

Similar fix as f8df1ab. For broken gzip
trailer, we should raise DataError even if the trailer is splitted into
multiple input chunks.

Reported by Atsuhiko Yamanaka at
https://twitter.com/#!/ymnk/status/109476173142179840 Thanks!

src/org/jruby/RubyZlib.java

@@ -547,10 +547,10 @@ public void append(ByteList obj) {
                     flater.setInput(bytes);
                     input = new ByteList(bytes, false);
                 }
-                run(false);
             } else {
                 input.append(obj);
             }
+            run(false);
         }
 
         @JRubyMethod(name = "sync_point?")

test/test_zlib.rb

@@ -595,6 +595,15 @@ def test_wrong_length
       z.inflate(gzip)
     end
   end
+
+  def test_wrong_length_split_trailer
+    gzip = "\x1f\x8b\x08\x00\x1a\x96\xe0\x4c\x00\x03\xcb\x48\xcd\xc9\xc9\x07\x00\x86\xa6\x10\x36\x04\x00\x00"
+    z = Zlib::Inflate.new(Zlib::MAX_WBITS + 16)
+    assert_equal("hello", z.inflate(gzip))
+    assert_raise(Zlib::DataError) do
+      z.inflate("\x00")
+    end
+  end
 end
 
 # Test for MAX_WBITS + 32
@@ -686,4 +695,13 @@ def test_wrong_length
       z.inflate(gzip)
     end
   end
+
+  def test_wrong_length_split_trailer
+    gzip = "\x1f\x8b\x08\x00\x1a\x96\xe0\x4c\x00\x03\xcb\x48\xcd\xc9\xc9\x07\x00\x86\xa6\x10\x36\x04\x00\x00"
+    z = Zlib::Inflate.new(Zlib::MAX_WBITS + 32)
+    assert_equal("hello", z.inflate(gzip))
+    assert_raise(Zlib::DataError) do
+      z.inflate("\x00")
+    end
+  end
 end