Support content scheme uri for Chrome on Android

base/android/content_uri_utils.cc

Index: base/android/content_uri_utils.cc
diff --git a/base/android/content_uri_utils.cc b/base/android/content_uri_utils.cc
index 0e0c0ea6bb127840862a9e0689aa5a89be4a5950..0482feef891db38f3f6807fb9f9fba9126fcb936 100644
--- a/base/android/content_uri_utils.cc
+++ b/base/android/content_uri_utils.cc
@@ -35,4 +35,14 @@ File OpenContentUriForRead(const FilePath& content_uri) {
   return File(fd);
 }
 
+std::string GetContentUriMimeType(const FilePath& content_uri) {

[palmer, 2014/11/19 00:23:54]

The name "...uri" seems to conflict with the type FilePath. I'd expect a thing
named "...uri" to be a GURL or other URL/URI type. Is |content_uri| the path
component of a URL?

[qinmin, 2014/11/19 02:13:07]

There are some historic reasons. The previous patches about content URI are file
upload cases. We treat content URIs as a file, reading the content and get the
data. So content URI is currently only used in file related classes,  such as
FileStreamContext and FileUtil, e.g. Additionally, there are operations like
Open() on content URI to get file desciptors. That makes it more like a FilePath
rather than a GURL. So we just treat the "content://" scheme the same as a drive
letter on Windows.

+  JNIEnv* env = base::android::AttachCurrentThread();
+  ScopedJavaLocalRef<jstring> j_uri =
+      ConvertUTF8ToJavaString(env, content_uri.value());
+  ScopedJavaLocalRef<jstring> j_mime =
+      Java_ContentUriUtils_getMimeType(
+          env, base::android::GetApplicationContext(), j_uri.obj());
+  return base::android::ConvertJavaStringToUTF8(env, j_mime.obj());
+}
+
 }  // namespace base