Make dt_runpath work for libraries opened from apk

This patch also fixes realpath for libraries opened directly
from apks.

Bug: http://b/21960914
Bug: http://b/21961857
Change-Id: I35ade661c87f1d448191f385811f6e9fd3cacf11

linker/linker_utils.h

@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef __LINKER_UTILS_H
+#define __LINKER_UTILS_H
+
+#include <string>
+
+bool normalize_path(const char* path, std::string* normalized_path);
+
+#endif