Improve video thumbnail generation and handling on send side

For direct attach only

// FREEBIE

src/org/thoughtcrime/securesms/util/MediaUtil.java

@@ -1,8 +1,10 @@
 package org.thoughtcrime.securesms.util;
 
+import android.content.ContentResolver;
 import android.content.Context;
 import android.graphics.Bitmap;
 import android.net.Uri;
+import android.provider.MediaStore;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.text.TextUtils;
@@ -162,6 +164,33 @@ public class MediaUtil {
     return !TextUtils.isEmpty(contentType) && contentType.trim().startsWith("video/");
   }
 
+  public static boolean hasVideoThumbnail(Uri uri) {
+    Log.w(TAG, "Checking: " + uri);
+
+    if (uri == null || !ContentResolver.SCHEME_CONTENT.equals(uri.getScheme())) {
+      return false;
+    }
+
+    if ("com.android.providers.media.documents".equals(uri.getAuthority())) {
+      return uri.getLastPathSegment().contains("video");
+    }
+
+    return false;
+  }
+
+  public static @Nullable Bitmap getVideoThumbnail(Context context, Uri uri) {
+    if ("com.android.providers.media.documents".equals(uri.getAuthority())) {
+      long videoId = Long.parseLong(uri.getLastPathSegment().split(":")[1]);
+
+      return MediaStore.Video.Thumbnails.getThumbnail(context.getContentResolver(),
+                                                      videoId,
+                                                      MediaStore.Images.Thumbnails.MINI_KIND,
+                                                      null);
+    }
+
+    return null;
+  }
+
   public static @Nullable String getDiscreteMimeType(@NonNull String mimeType) {
     final String[] sections = mimeType.split("/", 2);
     return sections.length > 1 ? sections[0] : null;