From 75d2f29087e2338bac040776a358d9213c6a98ad Mon Sep 17 00:00:00 2001
From: Timothy Nikkel <tnikkel@gmail.com>
Date: Wed, 23 Sep 2020 15:04:07 +0000
Subject: [PATCH] Bug 1665332. Make sure to initialize all fields of the
 ZoomConstraints to the correct values on ZoomConstraintsClient in all cases.
 r=kats

The default constructor initializes the two bools to true.

Differential Revision: https://phabricator.services.mozilla.com/D91103
---
 layout/base/ZoomConstraintsClient.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/layout/base/ZoomConstraintsClient.cpp b/layout/base/ZoomConstraintsClient.cpp
index fc595ddaaf7f..34d4323ff012 100644
--- a/layout/base/ZoomConstraintsClient.cpp
+++ b/layout/base/ZoomConstraintsClient.cpp
@@ -40,7 +40,10 @@ using namespace mozilla::dom;
 using namespace mozilla::layers;
 
 ZoomConstraintsClient::ZoomConstraintsClient()
-    : mDocument(nullptr), mPresShell(nullptr) {}
+    : mDocument(nullptr),
+      mPresShell(nullptr),
+      mZoomConstraints(false, false, CSSToParentLayerScale(1.f),
+                       CSSToParentLayerScale(1.f)) {}
 
 ZoomConstraintsClient::~ZoomConstraintsClient() = default;
 
@@ -186,6 +189,9 @@ static mozilla::layers::ZoomConstraints ComputeZoomConstraintsFromViewportInfo(
 }
 
 void ZoomConstraintsClient::RefreshZoomConstraints() {
+  mZoomConstraints = ZoomConstraints(false, false, CSSToParentLayerScale(1.f),
+                                     CSSToParentLayerScale(1.f));
+
   nsIWidget* widget = GetWidget(mPresShell);
   if (!widget) {
     return;