Previously, SkTextBlob was built on every paint in
DisplayListPlayerSkia::draw_glyph_run(), which meant:
- Repeated work when the same display list is painted multiple times
- Glyph arrays were allocated and populated on each paint
Now the blob is built once during display list recording and cached in
GlyphRun.
Move the visual viewport (pinch-to-zoom) transform from a reserved slot
in DisplayList to the AccumulatedVisualContext tree as a root transform
node. Fixed position elements now correctly inherit from this context.
This requires rebuilding the context tree and display list on each zoom
change, but this overhead will be eliminated by future partial context
tree rebuilds.
AccumulatedVisualContext nodes capture a snapshot of the current
clip-path when the tree is built, so we must invalidate whenever the
clip-path changes.
Fixes regression introduced in 98afd82
This test verifies that modifying clip-path via JavaScript properly
invalidates the accumulated visual context. Currently fails because the
clip-path in the display list remains unchanged after the style update.
Regression from 98afd82491.
