[Android] Initialize bottom controls synchronously to fix progress bar (#35464)

The deferred PostTask introduced to avoid ANR was causing the bottom
controls to be initialized after the progress bar, breaking it.
Revert to synchronous initialization.

Resolves: https://github.com/brave/brave-browser/issues/54458

android/java/org/chromium/chrome/browser/toolbar/BraveToolbarManager.java

@@ -24,8 +24,6 @@ import org.chromium.base.supplier.NullableObservableSupplier;
 import org.chromium.base.supplier.OneshotSupplier;
 import org.chromium.base.supplier.SettableMonotonicObservableSupplier;
 import org.chromium.base.supplier.SettableNonNullObservableSupplier;
-import org.chromium.base.task.PostTask;
-import org.chromium.base.task.TaskTraits;
 import org.chromium.build.annotations.Nullable;
 import org.chromium.cc.input.BrowserControlsState;
 import org.chromium.chrome.R;
@@ -324,15 +322,7 @@ public class BraveToolbarManager extends ToolbarManager
                 return;
             }
         }
-        // Defer bottom controls inflation to avoid ANR from GPU contention
-        // during startup. All consumers null-check the coordinator supplier.
-        // The bottom toolbar starts with visibility="gone", so the one-frame
-        // delay is imperceptible to the user. Using makeCancelable ensures
-        // the task is auto-cancelled when mCallbackController.destroy() is
-        // called during Activity teardown, preventing use-after-destroy.
-        PostTask.postTask(
-                TaskTraits.UI_DEFAULT,
-                mCallbackController.makeCancelable(this::initBraveBottomControls));
+        initBraveBottomControls();
     }
 
     private void initBraveBottomControls() {