Replace a few hard-coded strings with their constant counterparts.

ui/android/java/src/org/chromium/ui/SelectFileDialog.java

Index: ui/android/java/src/org/chromium/ui/SelectFileDialog.java
diff --git a/ui/android/java/src/org/chromium/ui/SelectFileDialog.java b/ui/android/java/src/org/chromium/ui/SelectFileDialog.java
index a9b117bb641a1b1f4b13ce8284fb71fb43f4fc1f..85e355dd1f4041a2d4eb688f5a333fc420c004b6 100644
--- a/ui/android/java/src/org/chromium/ui/SelectFileDialog.java
+++ b/ui/android/java/src/org/chromium/ui/SelectFileDialog.java
@@ -89,19 +89,19 @@ class SelectFileDialog implements WindowAndroid.IntentCallback{
             // chooser above.
             if (shouldShowImageTypes()) {
                 extraIntents.add(camera);
-                getContentIntent.setType("image/*");
+                getContentIntent.setType(ALL_IMAGE_TYPES);
             } else if (shouldShowVideoTypes()) {
                 extraIntents.add(camcorder);
-                getContentIntent.setType("video/*");
+                getContentIntent.setType(ALL_VIDEO_TYPES);
             } else if (shouldShowAudioTypes()) {
                 extraIntents.add(soundRecorder);
-                getContentIntent.setType("audio/*");
+                getContentIntent.setType(ALL_AUDIO_TYPES);
             }
         }
 
         if (extraIntents.isEmpty()) {
             // We couldn't resolve an accept type, so fallback to a generic chooser.
-            getContentIntent.setType("*/*");
+            getContentIntent.setType(ANY_TYPES);
             extraIntents.add(camera);
             extraIntents.add(camcorder);
             extraIntents.add(soundRecorder);