[Downloads] Open media downloads internally

chrome/android/java/src/org/chromium/chrome/browser/download/ui/DownloadFilter.java

Index: chrome/android/java/src/org/chromium/chrome/browser/download/ui/DownloadFilter.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/download/ui/DownloadFilter.java b/chrome/android/java/src/org/chromium/chrome/browser/download/ui/DownloadFilter.java
index 40387af4a4ec82f6ba8fda8641a0130fa74778f8..bafc31a86ec0785ec84d8417fbaf4a965dbc3def 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/download/ui/DownloadFilter.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/download/ui/DownloadFilter.java
@@ -10,6 +10,8 @@ import org.chromium.base.Log;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.UrlConstants;
 
+import java.util.Locale;
+
 /**
  * A class holding constants and convenience methods about filters and their corresponding
  * resources.
@@ -26,6 +28,11 @@ public class DownloadFilter {
     static final int FILTER_OTHER = 6;
     public static final int FILTER_BOUNDARY = 7;
 
+    private static final String MIMETYPE_VIDEO = "video";
+    private static final String MIMETYPE_AUDIO = "audio";
+    private static final String MIMETYPE_IMAGE = "image";
+    private static final String MIMETYPE_DOCUMENT = "text";
+
     /**
      * Icons and labels for each filter in the menu.
      *
@@ -91,4 +98,24 @@ public class DownloadFilter {
         }
         return result;
     }
+
+    /** Identifies the type of file represented by the given MIME type string. */
+    public static int fromMimeType(String mimeType) {
+        if (TextUtils.isEmpty(mimeType)) return DownloadFilter.FILTER_OTHER;
+
+        String[] pieces = mimeType.toLowerCase(Locale.getDefault()).split("/");
+        if (pieces.length != 2) return DownloadFilter.FILTER_OTHER;
+
+        if (MIMETYPE_VIDEO.equals(pieces[0])) {
+            return DownloadFilter.FILTER_VIDEO;
+        } else if (MIMETYPE_AUDIO.equals(pieces[0])) {
+            return DownloadFilter.FILTER_AUDIO;
+        } else if (MIMETYPE_IMAGE.equals(pieces[0])) {
+            return DownloadFilter.FILTER_IMAGE;
+        } else if (MIMETYPE_DOCUMENT.equals(pieces[0])) {
+            return DownloadFilter.FILTER_DOCUMENT;
+        } else {
+            return DownloadFilter.FILTER_OTHER;
+        }
+    }
 }