Use the fullscreen preferred size when reporting screen dimensions

https://bugs.webkit.org/show_bug.cgi?id=249297
<rdar://99403187>

Reviewed by Megan Gardner.

When we have a preferred size for fullscreen windows, use it when
reporting the screen dimensions to the page.

* Source/WebKit/UIProcess/WebPageProxy.h:
Expose `overrideScreenSize`.

* Source/WebKit/UIProcess/ios/WebPageProxyIOS.mm:
(WebKit::WebPageProxy::overrideScreenSize):
Read the fullscreen preferred size and override the screen size with it.

* Source/WebKit/UIProcess/ios/fullscreen/WKFullScreenWindowControllerIOS.mm:
(-[WKFullScreenWindowController enterFullScreen:]):
Use the (modified) page's screen size as target size for the fullscreen
window.

Canonical link: https://commits.webkit.org/258005@main

Source/WebKit/UIProcess/WebPageProxy.h

@@ -857,6 +857,8 @@ class WebPageProxy final : public API::ObjectImpl<API::Object::Type::Page>
     void scrollingNodeScrollWillStartScroll(WebCore::ScrollingNodeID);
     void scrollingNodeScrollDidEndScroll(WebCore::ScrollingNodeID);
 
+    WebCore::FloatSize overrideScreenSize();
+
     void dynamicViewportSizeUpdate(const WebCore::FloatSize& viewLayoutSize, const WebCore::FloatSize& minimumUnobscuredSize, const WebCore::FloatSize& maximumUnobscuredSize, const WebCore::FloatRect& targetExposedContentRect, const WebCore::FloatRect& targetUnobscuredRect, const WebCore::FloatRect& targetUnobscuredRectInScrollViewCoordinates, const WebCore::FloatBoxExtent& unobscuredSafeAreaInsets, double targetScale, int32_t deviceOrientation, double minimumEffectiveDeviceWidth, DynamicViewportSizeUpdateID);
 
     void setViewportConfigurationViewLayoutSize(const WebCore::FloatSize&, double scaleFactor, double minimumEffectiveDeviceWidth);
@@ -2529,7 +2531,6 @@ class WebPageProxy final : public API::ObjectImpl<API::Object::Type::Page>
 #if PLATFORM(IOS_FAMILY)
     WebCore::FloatSize screenSize();
     WebCore::FloatSize availableScreenSize();
-    WebCore::FloatSize overrideScreenSize();
     float textAutosizingWidth();
 
     void couldNotRestorePageState();

Source/WebKit/UIProcess/ios/WebPageProxyIOS.mm

@@ -85,6 +85,10 @@
 
 #define WEBPAGEPROXY_RELEASE_LOG(channel, fmt, ...) RELEASE_LOG(channel, "%p - [pageProxyID=%llu, webPageID=%llu, PID=%i] WebPageProxy::" fmt, this, m_identifier.toUInt64(), m_webPageID.toUInt64(), m_process->processIdentifier(), ##__VA_ARGS__)
 
+#if HAVE(UIKIT_WEBKIT_INTERNALS)
+static constexpr CGFloat kTargetFullscreenAspectRatio = 1.7778;
+#endif
+
 namespace WebKit {
 using namespace WebCore;
 
@@ -891,6 +895,13 @@ static bool exceedsRenderTreeSizeSizeThreshold(uint64_t thresholdSize, uint64_t
 
 FloatSize WebPageProxy::overrideScreenSize()
 {
+#if HAVE(UIKIT_WEBKIT_INTERNALS)
+    // Report screen dimensions based on fullscreen preferences.
+    CGFloat preferredWidth = m_preferences->mediaPreferredFullscreenWidth();
+    CGFloat preferredHeight = preferredWidth / kTargetFullscreenAspectRatio;
+    return FloatSize(CGSizeMake(preferredWidth, preferredHeight));
+#endif
+
     return WebCore::overrideScreenSize();
 }
 

Source/WebKit/UIProcess/ios/fullscreen/WKFullScreenWindowControllerIOS.mm

@@ -165,7 +165,6 @@ void store(WKWebView* webView)
 static constexpr NSTimeInterval kAnimationDuration = 0.2;
 #if HAVE(UIKIT_WEBKIT_INTERNALS)
 static constexpr CGFloat kFullScreenWindowCornerRadius = 12;
-static constexpr CGFloat kTargetWindowAspectRatio = 1.7778;
 #endif
 
 #pragma mark -
@@ -564,14 +563,16 @@ - (void)enterFullScreen:(CGSize)videoDimensions
     [_window setWindowLevel:UIWindowLevelNormal - 1];
     [_window setHidden:NO];
 #if HAVE(UIKIT_WEBKIT_INTERNALS)
-    CGFloat preferredWidth = page->preferences().mediaPreferredFullscreenWidth();
-    CGFloat preferredHeight = preferredWidth / kTargetWindowAspectRatio;
-    CGFloat videoAspectRatio = videoDimensions.height ? (videoDimensions.width / videoDimensions.height) : kTargetWindowAspectRatio;
+    auto screenSize = page->overrideScreenSize();
+    CGFloat preferredWidth = screenSize.width();
+    CGFloat preferredHeight = screenSize.height();
+    CGFloat preferredAspectRatio = preferredWidth / preferredHeight;
+    CGFloat videoAspectRatio = videoDimensions.height ? (videoDimensions.width / videoDimensions.height) : preferredAspectRatio;
 
     CGFloat targetWidth = preferredWidth;
     CGFloat targetHeight = preferredHeight;
     if (videoDimensions.height && videoDimensions.width) {
-        if (videoAspectRatio > kTargetWindowAspectRatio)
+        if (videoAspectRatio > preferredAspectRatio)
             targetHeight = videoDimensions.height * preferredWidth / videoDimensions.width;
         else
             targetWidth = videoDimensions.width * preferredHeight / videoDimensions.height;