Fix compilation errors in libmedia, libstagefright.

(invalid conversion from 'const char*' to 'char*')

Change-Id: Idef85606b7cff629b2778ed8134c79c892af54c2

media/libmedia/MediaScanner.cpp

@@ -77,13 +77,13 @@ status_t MediaScanner::processDirectory(
 }
 
 static bool fileMatchesExtension(const char* path, const char* extensions) {
-    char* extension = strrchr(path, '.');
+    const char* extension = strrchr(path, '.');
     if (!extension) return false;
     ++extension;    // skip the dot
     if (extension[0] == 0) return false;
 
     while (extensions[0]) {
-        char* comma = strchr(extensions, ',');
+        const char* comma = strchr(extensions, ',');
         size_t length = (comma ? comma - extensions : strlen(extensions));
         if (length == strlen(extension) && strncasecmp(extension, extensions, length) == 0) return true;
         extensions += length;

media/libstagefright/HTTPDataSource.cpp

@@ -158,7 +158,7 @@ HTTPDataSource::HTTPDataSource(
     string path;
     int port;
 
-    char *slash = strchr(uri + 7, '/');
+    const char *slash = strchr(uri + 7, '/');
     if (slash == NULL) {
         host = uri + 7;
         path = "/";
@@ -167,7 +167,7 @@ HTTPDataSource::HTTPDataSource(
         path = slash;
     }
 
-    char *colon = strchr(host.c_str(), ':');
+    const char *colon = strchr(host.c_str(), ':');
     if (colon == NULL) {
         port = 80;
     } else {