Fix pending transaction (#19733)

Author: Pavneet Singh

android/java/org/chromium/chrome/browser/crypto_wallet/fragments/PortfolioFragment.java

@@ -195,6 +195,8 @@ private void setUpObservers() {
                     mPendingTxs = transactionInfos;
                     if (mCurrentPendingTx == null && mPendingTxs.size() > 0) {
                         mCurrentPendingTx = mPendingTxs.get(0);
+                    } else if (mPendingTxs.size() == 0) {
+                        mCurrentPendingTx = null;
                     }
                     updatePendingTxNotification();
                 });
@@ -397,7 +399,7 @@ public void callAnotherApproveDialog() {
                                 .getAccountNameForTransaction(mCurrentPendingTx));
         approveTxBottomSheetDialogFragment.setApprovedTxObserver(this);
         approveTxBottomSheetDialogFragment.show(
-                getFragmentManager(), ApproveTxBottomSheetDialogFragment.TAG_FRAGMENT);
+                getParentFragmentManager(), ApproveTxBottomSheetDialogFragment.TAG_FRAGMENT);
     }
 
     private void showEditVisibleDialog() {