android: Implement nativeResourceForContext

To bring the plugin on par with xcb and eglfs in this regard.

New code has a better way to query these via
QOpenGLContext::nativeInterface() (or, more correctly, will have a
better way once the ability to query the config and display is added
in a follow up patch), but having some symmetry between the EGL-based
plugins won't hurt.

This is relevant in particular with OpenXR: not knowing the EGLConfig
makes it impossible to use the API on Android:
https://www.khronos.org/registry/OpenXR/specs/1.0/html/xrspec.html#XrGraphicsBindingOpenGLESAndroidKHR

Pick-to: 6.2
Change-Id: I163aed070096a4b58d3f650906c2f70ea31b3231
Reviewed-by: Andy Nichols <andy.nichols@qt.io>

src/plugins/platforms/android/qandroidplatformintegration.cpp

@@ -143,6 +143,19 @@ void *QAndroidPlatformNativeInterface::nativeResourceForWindow(const QByteArray
     return nullptr;
 }
 
+void *QAndroidPlatformNativeInterface::nativeResourceForContext(const QByteArray &resource, QOpenGLContext *context)
+{
+    if (QEGLPlatformContext *platformContext = static_cast<QEGLPlatformContext *>(context->handle())) {
+        if (resource == "eglcontext")
+            return platformContext->eglContext();
+        else if (resource == "eglconfig")
+            return platformContext->eglConfig();
+        else if (resource == "egldisplay")
+            return platformContext->eglDisplay();
+    }
+    return nullptr;
+}
+
 void QAndroidPlatformNativeInterface::customEvent(QEvent *event)
 {
     if (event->type() != QEvent::User)

src/plugins/platforms/android/qandroidplatformintegration.h

@@ -65,6 +65,7 @@ class QAndroidPlatformNativeInterface: public QPlatformNativeInterface
 public:
     void *nativeResourceForIntegration(const QByteArray &resource) override;
     void *nativeResourceForWindow(const QByteArray &resource, QWindow *window) override;
+    void *nativeResourceForContext(const QByteArray &resource, QOpenGLContext *context) override;
     std::shared_ptr<AndroidStyle> m_androidStyle;
 
 protected: