Bug 1753995 - Remove nsDOMWindowUtils.screenPixelsPerCSSPixel. r=smaug,dholbert

For all purposes, this is the same as devicePixelRatio. It was meant to
skip the resistFingerprinting check the devicePixelRatio getter does,
but we do that now using CallerType in WebIDL, so if we cared about that
for these tests (which we don't) we could just do
SpecialPowers.wrap(window).devicePixelRatio.

As a follow-up we could move the NoOverride to window for symmetry. But
it's only used by devtools touch simulation so not sure if worth it.

Differential Revision: https://phabricator.services.mozilla.com/D138021

accessible/tests/browser/Layout.jsm

@@ -121,8 +121,7 @@ const Layout = {
   },
 
   CSSToDevicePixels(win, x, y, width, height) {
-    const winUtil = win.windowUtils;
-    const ratio = winUtil.screenPixelsPerCSSPixel;
+    const ratio = win.devicePixelRatio;
 
     // CSS pixels and ratio can be not integer. Device pixels are always integer.
     // Do our best and hope it works.

accessible/tests/mochitest/layout.js

@@ -371,9 +371,7 @@ function getBoundsForDOMElm(aID) {
 }
 
 function CSSToDevicePixels(aWindow, aX, aY, aWidth, aHeight) {
-  var winUtil = aWindow.windowUtils;
-
-  var ratio = winUtil.screenPixelsPerCSSPixel;
+  var ratio = aWindow.devicePixelRatio;
 
   // CSS pixels and ratio can be not integer. Device pixels are always integer.
   // Do our best and hope it works.

dom/base/nsDOMWindowUtils.cpp

@@ -2189,19 +2189,6 @@ nsDOMWindowUtils::GetViewId(Element* aElement, nsViewID* aResult) {
   return NS_ERROR_NOT_AVAILABLE;
 }
 
-NS_IMETHODIMP
-nsDOMWindowUtils::GetScreenPixelsPerCSSPixel(float* aScreenPixels) {
-  nsCOMPtr<nsPIDOMWindowOuter> window = do_QueryReferent(mWindow);
-  NS_ENSURE_TRUE(window, NS_ERROR_FAILURE);
-  nsCOMPtr<nsPIDOMWindowInner> innerWindow = window->GetCurrentInnerWindow();
-  NS_ENSURE_STATE(innerWindow);
-  // XXX Why does this API exist? Callers should just use devicePixelRatio!
-  *aScreenPixels =
-      nsGlobalWindowInner::Cast(innerWindow)
-          ->GetDevicePixelRatio(CallerType::System, IgnoreErrors());
-  return NS_OK;
-}
-
 NS_IMETHODIMP
 nsDOMWindowUtils::GetScreenPixelsPerCSSPixelNoOverride(float* aScreenPixels) {
   nsPresContext* presContext = GetPresContext();

dom/base/test/file_toScreenRect.html

@@ -31,8 +31,7 @@ add_task(async () => {
   SpecialPowers.setFullZoom(window, 2.0);
 
   const rect = target.getBoundingClientRect();
-  const screenPixelsPerCSSPixel =
-    SpecialPowers.DOMWindowUtils.screenPixelsPerCSSPixel;
+  const screenPixelsPerCSSPixel = window.devicePixelRatio;
   const screenPixelsPerCSSPixelNoOverride =
     SpecialPowers.DOMWindowUtils.screenPixelsPerCSSPixelNoOverride;
 

dom/events/test/test_event_screenXY_in_cross_origin_iframe.html

@@ -9,13 +9,11 @@
 <iframe width=100></iframe>
 <iframe width=100></iframe>
 <script>
-const utils = SpecialPowers.DOMWindowUtils;
-
 function getScreenPosition(aElement, aOffsetX, aOffsetY) {
   const rect = aElement.getBoundingClientRect();
   const x = aOffsetX + window.mozInnerScreenX + rect.left;
   const y = aOffsetY + window.mozInnerScreenY + rect.top;
-  const scale = utils.screenPixelsPerCSSPixel;
+  const scale = window.devicePixelRatio;
   return [Math.round(x * scale), Math.round(y * scale)];
 }
 

dom/events/test/test_focus_blur_on_click_in_cross_origin_iframe.html

@@ -12,13 +12,11 @@ SimpleTest.requestLongerTimeout(2);
 
 let state = "start";
 
-const utils = SpecialPowers.DOMWindowUtils;
-
 function getScreenPosition(aElement, aOffsetX, aOffsetY) {
   const rect = aElement.getBoundingClientRect();
   const x = aOffsetX + window.mozInnerScreenX + rect.left;
   const y = aOffsetY + window.mozInnerScreenY + rect.top;
-  const scale = utils.screenPixelsPerCSSPixel;
+  const scale = window.devicePixelRatio;
   return [Math.round(x * scale), Math.round(y * scale)];
 }
 

dom/events/test/test_focus_blur_on_click_in_deep_cross_origin_iframe.html

@@ -10,8 +10,7 @@
 <script>
 let state = "start";
 
-const utils = SpecialPowers.DOMWindowUtils;
-const scale = utils.screenPixelsPerCSSPixel;
+const scale = window.devicePixelRatio;
 
 function getScreenPosition(aElement, aOffsetX, aOffsetY) {
   const rect = aElement.getBoundingClientRect();

dom/interfaces/base/nsIDOMWindowUtils.idl

@@ -1154,15 +1154,6 @@ interface nsIDOMWindowUtils : nsISupports {
    */
   readonly attribute Node nodeObservedByIMEContentObserver;
 
-  /**
-   * Get the number of screen pixels per CSS pixel.
-   *
-   * This is the same as window.devicePixelRatio, except it bypasses
-   * the fingerprinting resistance efforts that window.devicePixelRatio
-   * does (which is fine as this is only exposed to browser internals).
-   */
-  readonly attribute float screenPixelsPerCSSPixel;
-
   /**
    * Get the number of screen pixels per CSS pixel,
    * not taking into account any override of the device pixel scale

dom/tests/mochitest/general/test_innerScreen.xhtml

@@ -35,8 +35,7 @@ function doTests()
   catch(ex) { }
   ok(!readable, "window pixels per css pixel shouldn't be readable to content");
 
-  var domWindowUtils = window.windowUtils;
-  var devPxPerCSSPx = domWindowUtils.screenPixelsPerCSSPixel;
+  var devPxPerCSSPx = window.devicePixelRatio;
 
   is(window.devicePixelRatio, devPxPerCSSPx, "window.devicePixelRatio");
 
@@ -59,8 +58,7 @@ function doTests()
             "frame screen Y");
 
   fbc.fullZoom *= 2;
-  var frameDomWindowUtils = f.contentWindow.windowUtils;
-  is(frameDomWindowUtils.screenPixelsPerCSSPixel, 2*devPxPerCSSPx,
+  is(f.contentWindow.devicePixelRatio, 2*devPxPerCSSPx,
      "frame screen pixels per CSS pixel");
 
   is(f.contentWindow.devicePixelRatio, 2*devPxPerCSSPx, "frame devicePixelRatio");

gfx/layers/apz/test/mochitest/apz_test_native_event_utils.js

@@ -323,7 +323,7 @@ async function coordinatesRelativeToScreen(aParams) {
     // document, not to mozInnerScreen{X,Y}.
     const utils = SpecialPowers.getDOMWindowUtils(window);
     const resolution = await getResolution();
-    const deviceScale = utils.screenPixelsPerCSSPixel;
+    const deviceScale = window.devicePixelRatio;
     const deviceScaleNoOverride = utils.screenPixelsPerCSSPixelNoOverride;
     return {
       x:

gfx/layers/apz/test/mochitest/helper_doubletap_zoom_bug1702464.html

@@ -12,8 +12,7 @@
 async function test() {
   let useTouchpad = (location.search == "?touchpad");
 
-  const utils = SpecialPowers.getDOMWindowUtils(window);
-  const deviceScale = utils.screenPixelsPerCSSPixel;
+  const deviceScale = window.devicePixelRatio;
   let target2 = document.getElementById("target2")
 
   info("deviceScale " + deviceScale);

gfx/layers/apz/test/mochitest/helper_hittest_overscroll_contextmenu.html

@@ -99,7 +99,7 @@ async function test() {
   // on both the browser chrome window and the content window.
   // This makes sure we catch the case where the overscroll transform causes
   // the event to incorrectly target the browser chrome.
-  let deviceScale = utils.screenPixelsPerCSSPixel;
+  let deviceScale = window.devicePixelRatio;
   let midGutter = 4 / deviceScale;  // gutter is 8 *screen* pixels
   startListeningForContextmenuEventsInChrome();
   let contentReceivedContextmenu = false;

gfx/tests/mochitest/test_bug513439.html

@@ -21,12 +21,11 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=513439
 
 SimpleTest.waitForExplicitFinish();
 
-var domWindowUtils = SpecialPowers.DOMWindowUtils;
 SpecialPowers.pushPrefEnv({set: [["layout.css.devPixelsPerPx", "2"]]}, () => {
-  is(domWindowUtils.screenPixelsPerCSSPixel, 2, "devPixelsPerPx wasn't set correctly");
+  is(window.devicePixelRatio, 2, "devPixelsPerPx wasn't set correctly");
 
   SpecialPowers.pushPrefEnv({set: [["layout.css.devPixelsPerPx", "1.5"]]}, () => {
-    is(domWindowUtils.screenPixelsPerCSSPixel, 1.5, "devPixelsPerPx wasn't set correctly");
+    is(window.devicePixelRatio, 1.5, "devPixelsPerPx wasn't set correctly");
     SimpleTest.finish();
   });
 });

layout/base/tests/browser_select_popup_position_in_out_of_process_iframe.js

@@ -129,7 +129,7 @@ add_task(async function() {
   isfuzzy(
     popupRect.y,
     expectedYPosition,
-    window.windowUtils.screenPixelsPerCSSPixel,
+    window.devicePixelRatio,
     "y position of the popup"
   );
 

layout/style/test/test_media_queries.html

@@ -28,7 +28,7 @@ SimpleTest.requestLongerTimeout(2);
 var iframe;
 
 function getScreenPixelsPerCSSPixel() {
-  return SpecialPowers.DOMWindowUtils.screenPixelsPerCSSPixel;
+  return window.devicePixelRatio;
 }
 
 function run() {

layout/style/test/test_moz_device_pixel_ratio.html

@@ -38,16 +38,12 @@ function run() {
     return window.getComputedStyle(document.getElementById(divName)).visibility == "visible";
   }
 
-  function getScreenPixelsPerCSSPixel() {
-    return SpecialPowers.DOMWindowUtils.screenPixelsPerCSSPixel;
-  }
-
-  var screenPixelsPerCSSPixel = getScreenPixelsPerCSSPixel();
+  var screenPixelsPerCSSPixel = window.devicePixelRatio;
   var baseRatio = 1.0 * screenPixelsPerCSSPixel;
   var doubleRatio = 2.0 * screenPixelsPerCSSPixel;
   var halfRatio = 0.5 * screenPixelsPerCSSPixel;
   var styleElem = document.getElementsByTagName("style")[1];
-  styleElem.textContent = 
+  styleElem.textContent =
       ["@media all and (-moz-device-pixel-ratio: " + baseRatio + ") {",
          "#zoom1 { visibility: visible; }",
        "}",

layout/style/test/test_webkit_device_pixel_ratio.html

@@ -38,16 +38,12 @@ function run() {
     return window.getComputedStyle(document.getElementById(divName)).visibility == "visible";
   }
 
-  function getScreenPixelsPerCSSPixel() {
-    return SpecialPowers.DOMWindowUtils.screenPixelsPerCSSPixel;
-  }
-
-  var screenPixelsPerCSSPixel = getScreenPixelsPerCSSPixel();
+  var screenPixelsPerCSSPixel = window.devicePixelRatio;
   var baseRatio = 1.0 * screenPixelsPerCSSPixel;
   var doubleRatio = 2.0 * screenPixelsPerCSSPixel;
   var halfRatio = 0.5 * screenPixelsPerCSSPixel;
   var styleElem = document.getElementsByTagName("style")[1];
-  styleElem.textContent = 
+  styleElem.textContent =
       ["@media all and (-webkit-device-pixel-ratio: " + baseRatio + ") {",
          "#zoom1 { visibility: visible; }",
        "}",

layout/xul/test/test_bug987230.xhtml

@@ -61,8 +61,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=987230
     } else {
       //XXXgijs set mouse position back outside the iframe:
       let frameRect = window.frameElement.getBoundingClientRect();
-      let utils = window.windowUtils;
-      let scale = utils.screenPixelsPerCSSPixel;
+      let scale = window.devicePixelRatio;
       let outsideOfFrameX = (window.mozInnerScreenX + frameRect.width + 100) * scale;
       let outsideOfFrameY = Math.max(0, window.mozInnerScreenY - 100) * scale;
 

testing/mochitest/tests/SimpleTest/EventUtils.js

@@ -1032,7 +1032,7 @@ function synthesizeNativeTap(
     return;
   }
 
-  let scale = utils.screenPixelsPerCSSPixel;
+  let scale = aWindow.devicePixelRatio;
   let rect = aTarget.getBoundingClientRect();
   let x = (aWindow.mozInnerScreenX + rect.left + aOffsetX) * scale;
   let y = (aWindow.mozInnerScreenY + rect.top + aOffsetY) * scale;
@@ -1056,7 +1056,7 @@ function synthesizeNativeMouseEvent(aParams, aCallback = null) {
     atCenter, // Instead of offsetX/Y, synthesize the event at center of `target`
     screenX, // X offset in screen (in CSS pixels if `scale` is "screenPixelsPerCSSPixel*"), offsetX/Y nor atCenter must not be set if this is set
     screenY, // Y offset in screen (in CSS pixels if `scale` is "screenPixelsPerCSSPixel*"), offsetX/Y nor atCenter must not be set if this is set
-    // If scale is "screenPixelsPerCSSPixel", it'll be used.
+    // If scale is "screenPixelsPerCSSPixel", devicePixelRatio will be used.
     // If scale is "screenPixelsPerCSSPixelNoOverride", it'll be used.
     // If scale is "inScreenPixels", clientX/Y nor scaleX/Y are not adjusted with screenPixelsPerCSSPixel*.
     scale = "screenPixelsPerCSSPixel",
@@ -1117,7 +1117,7 @@ function synthesizeNativeMouseEvent(aParams, aCallback = null) {
       return 1.0;
     }
     if (scale === "screenPixelsPerCSSPixel") {
-      return utils.screenPixelsPerCSSPixel;
+      return win.devicePixelRatio;
     }
     if (scale === "screenPixelsPerCSSPixelNoOverride") {
       return utils.screenPixelsPerCSSPixelNoOverride;

widget/tests/test_panel_mouse_coords.xhtml

@@ -59,8 +59,8 @@ function sendMouseEvent() {
 }
 
 function checkCoords(event) {
-  isfuzzy(event.clientX, rect.left + 1, window.windowUtils.screenPixelsPerCSSPixel, "Motion x coordinate");
-  isfuzzy(event.clientY, rect.top + 2, window.windowUtils.screenPixelsPerCSSPixel, "Motion y coordinate");
+  isfuzzy(event.clientX, rect.left + 1, window.devicePixelRatio, "Motion x coordinate");
+  isfuzzy(event.clientY, rect.top + 2, window.devicePixelRatio, "Motion y coordinate");
   done();
 }