Add more offload tests

These test various clip scenarios.

testsuite/gsk/meson.build

@@ -466,6 +466,9 @@ if os_linux
     'stop_offloading.node',
     'source.node',
     'nested.node',
+    'clipped.node',
+    'not-clipped.node',
+    'complex-clip.node',
   ]
 
   foreach test : offload_tests

testsuite/gsk/offload/clipped.node

@@ -0,0 +1,9 @@
+clip {
+  clip: 10 10 10 10;
+  child: subsurface {
+    child: texture {
+      bounds: 0 0 20 20;
+      texture: url('data:image/svg+xml;utf-8,<svg width="20" height="20"></svg>');
+    }
+  }
+}

testsuite/gsk/offload/clipped.offload

@@ -0,0 +1 @@
+0: not offloaded

testsuite/gsk/offload/complex-clip.node

@@ -0,0 +1,18 @@
+rounded-clip {
+  clip: 0 0 50 50 / 20;
+  child: clip {
+    clip: 2 2 40 40;
+    child: container {
+      color {
+        color: white;
+        bounds: 0 0 50 50;
+      }
+      subsurface {
+        child: texture {
+          bounds: 10 10 20 20;
+          texture: url('data:image/svg+xml;utf-8,<svg width="20" height="20"></svg>');
+        }
+      }
+    }
+  }
+}

testsuite/gsk/offload/complex-clip.offload

@@ -0,0 +1 @@
+0: not offloaded

testsuite/gsk/offload/not-clipped.node

@@ -0,0 +1,9 @@
+clip {
+  clip: 0 0 50 50;
+  child: subsurface {
+    child: texture {
+      bounds: 0 0 20 20;
+      texture: url('data:image/svg+xml;utf-8,<svg width="20" height="20"></svg>');
+    }
+  }
+}

testsuite/gsk/offload/not-clipped.offload

@@ -0,0 +1 @@
+0: offloaded, raised, above: -, texture: 20x20, source: 0 0 20 20, dest: 0 0 20 20