Bug 4016329 do full string comparisons

Use full string comparisons instead of partial for
  file extension and MIME type.
Do case-insensitive comparison of MIME type and file extensions.
Fix error in comment for String8::getPathExtension.
Remove dead code -- StringTokenizer is unused.

Change-Id: I322be6235abbdaab5f7eafa48926dbb2cf46dc29
diff --git a/drm/libdrmframework/include/PlugInManager.h b/drm/libdrmframework/include/PlugInManager.h
index 9ad195f..8029138 100644
--- a/drm/libdrmframework/include/PlugInManager.h
+++ b/drm/libdrmframework/include/PlugInManager.h
@@ -230,11 +230,9 @@
      */
     bool isPlugIn(const struct dirent* pEntry) const {
         String8 sName(pEntry->d_name);
-        int extentionPos = sName.size() - String8(PLUGIN_EXTENSION).size();
-        if (extentionPos < 0) {
-            return false;
-        }
-        return extentionPos == (int)sName.find(PLUGIN_EXTENSION);
+        String8 extension(sName.getPathExtension());
+        // Note that the plug-in extension must exactly match case
+        return extension == String8(PLUGIN_EXTENSION);
     }
 
     /**
diff --git a/drm/libdrmframework/include/StringTokenizer.h b/drm/libdrmframework/include/StringTokenizer.h
deleted file mode 100644
index 70e7558..0000000
--- a/drm/libdrmframework/include/StringTokenizer.h
+++ /dev/null
@@ -1,87 +0,0 @@
-/*
- * Copyright (C) 2010 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 __STRING_TOKENIZER_H__
-#define __STRING_TOKENIZER_H__
-
-#include <drm/drm_framework_common.h>
-
-namespace android {
-
-/**
- * This is an utility class for String manipulation.
- *
- */
-class StringTokenizer {
-public:
-    /**
-     * Iterator for string tokens
-     */
-    class Iterator {
-        friend class StringTokenizer;
-    private:
-        Iterator(StringTokenizer* StringTokenizer)
-         : mStringTokenizer(StringTokenizer), mIndex(0) {}
-
-    public:
-        Iterator(const Iterator& iterator);
-        Iterator& operator=(const Iterator& iterator);
-        virtual ~Iterator() {}
-
-    public:
-        bool hasNext();
-        String8& next();
-
-    private:
-        StringTokenizer* mStringTokenizer;
-        unsigned int mIndex;
-    };
-
-public:
-    /**
-     * Constructor for StringTokenizer
-     *
-     * @param[in] string Complete string data
-     * @param[in] delimeter Delimeter used to split the string
-     */
-    StringTokenizer(const String8& string, const String8& delimeter);
-
-    /**
-     * Destructor for StringTokenizer
-     */
-    ~StringTokenizer() {}
-
-private:
-    /**
-     * Splits the string according to the delimeter
-     */
-    void splitString(const String8& string, const String8& delimeter);
-
-public:
-    /**
-     * Returns Iterator object to walk through the split string values
-     *
-     * @return Iterator object
-     */
-    Iterator iterator();
-
-private:
-    Vector<String8> mStringTokenizerVector;
-};
-
-};
-#endif /* __STRING_TOKENIZER_H__ */
-