Use the browser compositor for drawing windows on WASM

Make the browser compositor draw the window non-client area (using css
+ html). Get rid of OpenGL usage in non-OpenGL windows and use canvas
2d context instead to blit the texture (QImage).

Also, as part of the change, remove the deprecated canvas element support
in QScreen.

Fixes: QTBUG-107116
Fixes: QTBUG-107219
Change-Id: I65f0d91831c806315685ca681ac0e416673f5cd5
Reviewed-by: Morten Johan Sørvig <morten.sorvig@qt.io>
Reviewed-by: Aleksandr Reviakin <aleksandr.reviakin@qt.io>
Reviewed-by: David Skoland <david.skoland@qt.io>

1 files changed, 4 insertions, 3 deletions

diff --git a/src/plugins/platforms/wasm/qwasmaccessibility.cpp b/src/plugins/platforms/wasm/qwasmaccessibility.cpp
index 75e5b0a674..eb3e30b140 100644
--- a/src/plugins/platforms/wasm/qwasmaccessibility.cpp
+++ b/src/plugins/platforms/wasm/qwasmaccessibility.cpp
@@ -38,7 +38,7 @@ emscripten::val QWasmAccessibility::getContainer(QAccessibleInterface *iface)
     QWasmScreen *screen = QWasmScreen::get(window->screen());
     if (!screen)
         return emscripten::val::undefined();
-    return screen->container();
+    return screen->element();
 }
 
 emscripten::val QWasmAccessibility::getDocument(const emscripten::val &container)
@@ -142,11 +142,12 @@ void QWasmAccessibility::setHtmlElementGeometry(QAccessibleInterface *iface)
 void QWasmAccessibility::setHtmlElementGeometry(QAccessibleInterface *iface, emscripten::val element)
 {
     // Position the element using "position: absolute" in order to place
-    // it under the corresponding Qt element on the canvas.
+    // it under the corresponding Qt element in the screen.
     QRect geometry = iface->rect();
     emscripten::val style = element["style"];
     style.set("position", std::string("absolute"));
-    style.set("z-index", std::string("-1")); // FIXME: "0" should be sufficient to order beheind the canvas, but isn't
+    style.set("z-index", std::string("-1")); // FIXME: "0" should be sufficient to order beheind the
+                                             // screen element, but isn't
     style.set("left", std::to_string(geometry.x()) + "px");
     style.set("top", std::to_string(geometry.y()) + "px");
     style.set("width", std::to_string(geometry.width()) + "px");