showRenderTreeForThis should output PseudoId

https://bugs.webkit.org/show_bug.cgi?id=265769
rdar://119109505

Reviewed by Simon Fraser.

Saves countless time debugging anonymous renderers.

Sample output:
```
(B)lock/(I)nline/I(N)line-block, (A)bsolute/Fi(X)ed/(R)elative/Stic(K)y, (F)loating, (O)verflow clip, Anon(Y)mous, (G)enerated, has(L)ayer, hasLayer(S)crollableArea, (C)omposited, Content-visibility:(H)idden/(A)uto, (S)kipped content, (+)Dirty style, (+)Dirty layout
B---YGLSC-- -+  RenderView at (0,0) size 1420x763 renderer (0x117000ac0) layout box (0x0) layout->[normal child]
B-----LS--- -+    HTML RenderBlock at (0,0) size 1420x84 renderer (0x117001e80) layout box (0x0) node (0x117001700) layout->[normal child]
B---------- -+      BODY RenderBody at (8,16) size 1404x52 renderer (0x117002110) layout box (0x0) node (0x117001940) layout->[normal child]
B---------- -+        DIV RenderBlock at (0,0) size 1404x52 renderer (0x117003a50) layout box (0x0) node (0x117003740) layout->[normal child]
BX--YGL---- --*   RenderBlock (::view-transition) at (0,0) size 1420x763 renderer (0x117004c90) layout box (0x1170076c0)
---------- --      line at (0.00,0.00) size (1420.00x0.00) baseline (0.00) enclosing top (0.00) bottom (0.00)
---------- --        Root inline box at (0.00,-14.00) size (0.00x18.00)
---------- --        Run(s):
BA--YGL---- --      RenderBlock (::view-transition-group) at (200,200) size 100x100 renderer (0x117004f20) layout box (0x117007770)
---------- --        line at (0.00,0.00) size (100.00x0.00) baseline (0.00) enclosing top (0.00) bottom (0.00)
---------- --          Root inline box at (0.00,-14.00) size (0.00x18.00)
---------- --          Run(s):
BA--YGL---- --        RenderBlock (::view-transition-image-pair) at (0,0) size 50x50 renderer (0x1170051b0) layout box (0x1170078d0)
---------- --          line at (0.00,0.00) size (50.00x0.00) baseline (0.00) enclosing top (0.00) bottom (0.00)
---------- --            Root inline box at (0.00,-14.00) size (0.00x18.00)
---------- --            Run(s):
BA--YGL---- --          RenderBlock (::view-transition-old) at (0,0) size 20x20 renderer (0x117005440) layout box (0x117008910)
BA--YGL---- --          RenderBlock (::view-transition-new) at (0,0) size 20x20 renderer (0x1170056d0) layout box (0x1170089c0)
BA--YGL---- --      RenderBlock (::view-transition-group) at (500,500) size 100x100 renderer (0x117005960) layout box (0x117007820)
---------- --        line at (0.00,0.00) size (100.00x0.00) baseline (0.00) enclosing top (0.00) bottom (0.00)
---------- --          Root inline box at (0.00,-14.00) size (0.00x18.00)
---------- --          Run(s):
BA--YGL---- --        RenderBlock (::view-transition-image-pair) at (0,0) size 50x50 renderer (0x117005bf0) layout box (0x117009150)
---------- --          line at (0.00,0.00) size (50.00x0.00) baseline (0.00) enclosing top (0.00) bottom (0.00)
---------- --            Root inline box at (0.00,-14.00) size (0.00x18.00)
---------- --            Run(s):
BA--YGL---- --          RenderBlock (::view-transition-old) at (0,0) size 20x20 renderer (0x117005e80) layout box (0x1170098e0)
BA--YGL---- --          RenderBlock (::view-transition-new) at (0,0) size 20x20 renderer (0x117006110) layout box (0x117009990)
```

* Source/WebCore/rendering/RenderObject.cpp:
(WebCore::RenderObject::outputRenderObject const):

Canonical link: https://commits.webkit.org/271521@main

Source/WebCore/rendering/RenderObject.cpp

@@ -1344,6 +1344,9 @@ void RenderObject::outputRenderObject(TextStream& stream, bool mark, int depth)
     else
         stream << nameView;
 
+    if (style().styleType() != PseudoId::None)
+        stream << " (::" << style().styleType() << ")";
+
     if (is<RenderBox>(*this)) {
         auto& renderBox = downcast<RenderBox>(*this);
         FloatRect boxRect = renderBox.frameRect();