From d44e0b70462df3cdda9d4d89c39b4c2e2d89cb6d Mon Sep 17 00:00:00 2001
From: Edgar Chen <echen@mozilla.com>
Date: Sat, 15 Mar 2025 19:52:58 +0000
Subject: [PATCH] Bug 1952343 - Notify nsI{Color|File}PickerShownCallback
 asynchronously when picker is blocked; r=emilio

Otherwise, the HTMLInputElement doesn't handle the mPickerRunning flag right if
it is in parent process. There is no such problem on content process because
the IPC is async.

Differential Revision: https://phabricator.services.mozilla.com/D241440
---
 widget/nsBaseColorPicker.cpp |  7 +++++--
 widget/nsBaseFilePicker.cpp  | 11 +++++++++--
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/widget/nsBaseColorPicker.cpp b/widget/nsBaseColorPicker.cpp
index e6f10c8dfa6c..5c13bbe3c38c 100644
--- a/widget/nsBaseColorPicker.cpp
+++ b/widget/nsBaseColorPicker.cpp
@@ -7,6 +7,7 @@
 
 #include "mozilla/dom/BrowsingContext.h"
 #include "mozilla/dom/CanonicalBrowsingContext.h"
+#include "nsThreadUtils.h"
 
 NS_IMETHODIMP
 nsBaseColorPicker::Init(mozilla::dom::BrowsingContext* aBrowsingContext,
@@ -47,8 +48,10 @@ bool nsBaseColorPicker::MaybeBlockColorPicker(
   if (!mBrowsingContext->Canonical()->CanOpenModalPicker()) {
     if (aCallback) {
       // Color pickers are disabled, so we answer the callback with
-      // returnCancel.
-      aCallback->Done(EmptyString());
+      // empty string.
+      NS_DispatchToCurrentThread(mozilla::NewRunnableMethod<const nsAString&>(
+          "nsBaseColorPicker::CallbackWithEmptyString", aCallback,
+          &nsIColorPickerShownCallback::Done, EmptyString()));
     }
     return true;
   }
diff --git a/widget/nsBaseFilePicker.cpp b/widget/nsBaseFilePicker.cpp
index bed69bffc73b..7de814a376f0 100644
--- a/widget/nsBaseFilePicker.cpp
+++ b/widget/nsBaseFilePicker.cpp
@@ -26,6 +26,7 @@
 #include "WidgetUtils.h"
 #include "nsSimpleEnumerator.h"
 #include "nsContentUtils.h"
+#include "nsThreadUtils.h"
 
 #include "nsBaseFilePicker.h"
 
@@ -351,7 +352,10 @@ bool nsBaseFilePicker::MaybeBlockFilePicker(
   if (mozilla::StaticPrefs::widget_disable_file_pickers()) {
     if (aCallback) {
       // File pickers are disabled, so we answer the callback with returnCancel.
-      aCallback->Done(nsIFilePicker::returnCancel);
+      NS_DispatchToCurrentThread(
+          mozilla::NewRunnableMethod<nsIFilePicker::ResultCode>(
+              "nsBaseFilePicker::CallbackWithCancelResult", aCallback,
+              &nsIFilePickerShownCallback::Done, nsIFilePicker::returnCancel));
     }
 
     RefPtr<Element> topFrameElement = mBrowsingContext->GetTopFrameElement();
@@ -372,7 +376,10 @@ bool nsBaseFilePicker::MaybeBlockFilePicker(
   if (aCallback) {
     // File pickers are not allowed to open, so we respond to the callback with
     // returnCancel.
-    aCallback->Done(nsIFilePicker::returnCancel);
+    NS_DispatchToCurrentThread(
+        mozilla::NewRunnableMethod<nsIFilePicker::ResultCode>(
+            "nsBaseFilePicker::CallbackWithCancelResult", aCallback,
+            &nsIFilePickerShownCallback::Done, nsIFilePicker::returnCancel));
   }
 
   return true;