Description

• Dom canvas now uses flt-picture instead of creating extra dom-canvas node.
• computeDensity now uses isIdentityOrTranslation() to fix regression in update_many_child_layers benchmark.

═════════════════════════╡ ••• Final A/B results ••• ╞══════════════════════════
Score	Average A (noise)	Average B (noise)	Speed-up
bench_update_many_child_layers.html.drawFrameDuration.average	8641.60 (1.38%)	2418.36 (2.71%)	3.57x	
bench_update_many_child_layers.html.drawFrameDuration.outlierRatio	1.80 (5.63%)	1.10 (1.48%)	1.64x
bench_update_many_child_layers.html.totalUiFrame.average	28969.70 (0.66%)	9189.70 (1.25%)	3.15x

• Micro optimizations around global final domRenderer that does extra lazyinit lookup.
• Micro optimizations around style setting:

Before:
    apply$0: function() {
      var t1 = this.rootElement.style,
        t2 = "translate(" + H.S(this.dx) + "px, " + H.S(this.dy) + "px)";
      t1.toString;
      C.CssStyleDeclaration_methods._setPropertyHelper$3(t1, C.CssStyleDeclaration_methods._browserPropertyName$1(t1, "transform"), t2, "");
    },
After:
 apply$0: function() {
      var t2,
        t1 = this.rootElement;
      t1.toString;
      t2 = "translate(" + H.S(this.dx) + "px, " + H.S(this.dy) + "px)";
      t1.style.transform = t2;
    },

Related Issues

flutter/flutter#69910
flutter/flutter#59404

Tests

Covered by web_benchmarks.dart.

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