Auto merge of #21850 - servo:webgl, r=jdm

Don't use an intermediate PNG buffer in HTMLCanvasElement::ToDataURL

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1 files changed, 14 insertions, 1 deletions

diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs
index 2c395094e7f..a3c4c7814ea 100644
--- a/components/script/dom/bindings/trace.rs
+++ b/components/script/dom/bindings/trace.rs
@@ -261,7 +261,13 @@ unsafe impl<T: JSTraceable> JSTraceable for VecDeque<T> {
     }
 }
 
-unsafe impl<T: JSTraceable> JSTraceable for (T, T, T, T) {
+unsafe impl<A, B, C, D> JSTraceable for (A, B, C, D)
+where
+    A: JSTraceable,
+    B: JSTraceable,
+    C: JSTraceable,
+    D: JSTraceable,
+{
     unsafe fn trace(&self, trc: *mut JSTracer) {
         self.0.trace(trc);
         self.1.trace(trc);
@@ -616,6 +622,13 @@ unsafe impl<U> JSTraceable for TypedSize2D<f32, U> {
     }
 }
 
+unsafe impl<U> JSTraceable for TypedSize2D<u32, U> {
+    #[inline]
+    unsafe fn trace(&self, _trc: *mut JSTracer) {
+        // Do nothing
+    }
+}
+
 unsafe impl JSTraceable for StyleLocked<FontFaceRule> {
     unsafe fn trace(&self, _trc: *mut JSTracer) {
         // Do nothing.