Display modal permission prompts in RTL locales correctly.

This patch fixes modal permission prompts so that in RTL:
- The text direction is RTL as per the locale, instead of following the
  first strong directional character (typically the first character of
  the URL)
- The icon occurs on the right side of the dialog (i.e. before it)

Bug: 774926
Change-Id: I8677cf61c30bdce95113e0e414531c343ed302c2
Reviewed-on: https://chromium-review.googlesource.com/722382Reviewed-by: Bernhard Bauer <bauerb@chromium.org>
Commit-Queue: Timothy Loh <timloh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#509637}

chrome/android/java/res/layout/permission_dialog.xml

@@ -13,6 +13,7 @@
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:gravity="center_vertical"
+        android:textDirection="locale"
         android:textSize="@dimen/dialog_text_size"
         android:paddingBottom="24dp"
         android:drawablePadding="8dp" />

chrome/android/java/src/org/chromium/chrome/browser/permissions/PermissionDialogController.java

@@ -8,6 +8,7 @@ import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.content.DialogInterface;
 import android.support.annotation.IntDef;
+import android.support.v4.widget.TextViewCompat;
 import android.support.v7.app.AlertDialog;
 import android.support.v7.widget.SwitchCompat;
 import android.text.TextUtils;
@@ -149,8 +150,8 @@ public class PermissionDialogController implements AndroidPermissionRequester.Re
         messageTextView.setText(prepareMainMessageString(mDialogDelegate));
         messageTextView.setVisibility(View.VISIBLE);
         messageTextView.announceForAccessibility(mDialogDelegate.getMessageText());
-        messageTextView.setCompoundDrawablesWithIntrinsicBounds(
-                mDialogDelegate.getDrawableId(), 0, 0, 0);
+        TextViewCompat.setCompoundDrawablesRelativeWithIntrinsicBounds(
+                messageTextView, mDialogDelegate.getDrawableId(), 0, 0, 0);
 
         mSwitchView = (SwitchCompat) view.findViewById(R.id.permission_dialog_persist_toggle);
         mSwitchView.setChecked(true);