Allow OpenApkAsset() to open resource files as well as assets.

android_webview/native/aw_media_url_interceptor.cc

Index: android_webview/native/aw_media_url_interceptor.cc
diff --git a/android_webview/native/aw_media_url_interceptor.cc b/android_webview/native/aw_media_url_interceptor.cc
index 6923d69133e2578f5c48cca3254136e3e15af795..a2c1cddea8147dda8930b66b40264a5f5b3f9184 100644
--- a/android_webview/native/aw_media_url_interceptor.cc
+++ b/android_webview/native/aw_media_url_interceptor.cc
@@ -21,7 +21,8 @@ bool AwMediaUrlInterceptor::Intercept(const std::string& url,
 
   if (StartsWithASCII(url, asset_file_prefix, true)) {
     std::string filename(url);
-    ReplaceFirstSubstringAfterOffset(&filename, 0, asset_file_prefix, "");
+    ReplaceFirstSubstringAfterOffset(
+        &filename, 0, asset_file_prefix, "assets/");
     base::MemoryMappedFile::Region region =
         base::MemoryMappedFile::Region::kWholeFile;
     *fd = base::android::OpenApkAsset(filename, &region);