Add new column into Root to get the supported query args

DocumentsContract:
- Add @Public column Root#COLUMN_QUERY_ARGS
- Update java doc

DocumentsProvider:
- Update java doc

FileSystemProvider & ExternalStorageProvider
- Add supported query args into Roots

Bug: 121234248
Test: manual
Change-Id: Ia944200ee1a44d75c9ad683564218e3d0dcef885

api/current.txt

@@ -38007,6 +38007,7 @@ package android.provider {
     field public static final String COLUMN_FLAGS = "flags";
     field public static final String COLUMN_ICON = "icon";
     field public static final String COLUMN_MIME_TYPES = "mime_types";
+    field public static final String COLUMN_QUERY_ARGS = "query_args";
     field public static final String COLUMN_ROOT_ID = "root_id";
     field public static final String COLUMN_SUMMARY = "summary";
     field public static final String COLUMN_TITLE = "title";

core/java/android/provider/DocumentsContract.java

@@ -639,6 +639,28 @@ public final class DocumentsContract {
          */
         public static final String COLUMN_MIME_TYPES = "mime_types";
 
+        /**
+         * Query arguments supported by this root. This column is optional
+         * and related to {@link #COLUMN_FLAGS} and {@link #FLAG_SUPPORTS_SEARCH}.
+         * If the flags include {@link #FLAG_SUPPORTS_SEARCH}, and the column is
+         * {@code null}, the root is assumed to support {@link #QUERY_ARG_DISPLAY_NAME}
+         * search of {@link Document#COLUMN_DISPLAY_NAME}. Multiple query arguments
+         * can be separated by a newline. For example, a root supporting
+         * {@link #QUERY_ARG_MIME_TYPES} and {@link #QUERY_ARG_DISPLAY_NAME} might
+         * return "android:query-arg-mime-types\nandroid:query-arg-display-name".
+         * <p>
+         * Type: STRING
+         * @see #COLUMN_FLAGS
+         * @see #FLAG_SUPPORTS_SEARCH
+         * @see #QUERY_ARG_DISPLAY_NAME
+         * @see #QUERY_ARG_FILE_SIZE_OVER
+         * @see #QUERY_ARG_LAST_MODIFIED_AFTER
+         * @see #QUERY_ARG_MIME_TYPES
+         * @see DocumentsProvider#querySearchDocuments(String, String[],
+         *      Bundle)
+         */
+        public static final String COLUMN_QUERY_ARGS = "query_args";
+
         /**
          * MIME type for a root.
          */
@@ -680,6 +702,8 @@ public final class DocumentsContract {
          *      String)
          * @see DocumentsProvider#querySearchDocuments(String, String,
          *      String[])
+         * @see DocumentsProvider#querySearchDocuments(String, String[],
+         *      Bundle)
          */
         public static final int FLAG_SUPPORTS_SEARCH = 1 << 3;
 

core/java/android/provider/DocumentsProvider.java

@@ -687,6 +687,7 @@ public abstract class DocumentsProvider extends ContentProvider {
      *         extras {@link Bundle} when any QUERY_ARG_* value was honored
      *         during the preparation of the results.
      *
+     * @see Root#COLUMN_QUERY_ARGS
      * @see ContentResolver#EXTRA_HONORED_ARGS
      * @see DocumentsContract#EXTRA_LOADING
      * @see DocumentsContract#EXTRA_INFO

core/java/com/android/internal/content/FileSystemProvider.java

@@ -74,6 +74,16 @@ public abstract class FileSystemProvider extends DocumentsProvider {
 
     private static final boolean LOG_INOTIFY = false;
 
+    protected static final String SUPPORTED_QUERY_ARGS = joinNewline(
+            DocumentsContract.QUERY_ARG_DISPLAY_NAME,
+            DocumentsContract.QUERY_ARG_FILE_SIZE_OVER,
+            DocumentsContract.QUERY_ARG_LAST_MODIFIED_AFTER,
+            DocumentsContract.QUERY_ARG_MIME_TYPES);
+
+    private static String joinNewline(String... args) {
+        return TextUtils.join("\n", args);
+    }
+
     private String[] mDefaultProjection;
 
     @GuardedBy("mObservers")

packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java

@@ -76,7 +76,7 @@ public class ExternalStorageProvider extends FileSystemProvider {
 
     private static final String[] DEFAULT_ROOT_PROJECTION = new String[] {
             Root.COLUMN_ROOT_ID, Root.COLUMN_FLAGS, Root.COLUMN_ICON, Root.COLUMN_TITLE,
-            Root.COLUMN_DOCUMENT_ID, Root.COLUMN_AVAILABLE_BYTES,
+            Root.COLUMN_DOCUMENT_ID, Root.COLUMN_AVAILABLE_BYTES, Root.COLUMN_QUERY_ARGS
     };
 
     private static final String[] DEFAULT_DOCUMENT_PROJECTION = new String[] {
@@ -444,6 +444,7 @@ public class ExternalStorageProvider extends FileSystemProvider {
                 row.add(Root.COLUMN_FLAGS, root.flags);
                 row.add(Root.COLUMN_TITLE, root.title);
                 row.add(Root.COLUMN_DOCUMENT_ID, root.docId);
+                row.add(Root.COLUMN_QUERY_ARGS, SUPPORTED_QUERY_ARGS);
 
                 long availableBytes = -1;
                 if (root.reportAvailableBytes) {