[web] consolidate JS interop code (flutter#30007)

* Consolidate and check JavaScript access
* Remove all `ignore: implicit_dynamic_function`
* Add `js_access_test.dart` that validates JS access
* Make `engine.dart` an exports-only library
* Fix `sdk_rewriter_test.dart` and `ci/analyze.sh` (they skipped some tests)

ci/analyze.sh

@@ -77,6 +77,11 @@ echo ""
 echo ""
 
 # Check that dart libraries conform.
-echo "Checking web_ui api conformance..."
+echo "Checking the integrity of the Web SDK"
 (cd "$FLUTTER_DIR/web_sdk"; "$DART" pub get)
-(cd "$FLUTTER_DIR"; "$DART" "web_sdk/test/api_conform_test.dart")
+WEB_SDK_TEST_FILES="$FLUTTER_DIR/web_sdk/test/*"
+for testFile in $WEB_SDK_TEST_FILES
+do
+  echo "Running $testFile"
+  (cd "$FLUTTER_DIR"; FLUTTER_DIR="$FLUTTER_DIR" "$DART" --enable-asserts $testFile)
+done

ci/licenses_golden/licenses_flutter

@@ -528,7 +528,6 @@ FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/color_filter.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/debug_canvas_reuse_overlay.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/dom_canvas.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/image_filter.dart
-FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/offscreen_canvas.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/offset.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/opacity.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/painting.dart
@@ -555,11 +554,11 @@ FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/shaders/normalized_gradien
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/shaders/shader.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/shaders/shader_builder.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/shaders/vertex_shaders.dart
-FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/shaders/webgl_context.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/surface.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/surface_stats.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html/transform.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/html_image_codec.dart
+FILE: ../../../flutter/lib/web_ui/lib/src/engine/initialization.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/key_map.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/keyboard.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/keyboard_binding.dart
@@ -580,6 +579,7 @@ FILE: ../../../flutter/lib/web_ui/lib/src/engine/pointer_binding.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/pointer_converter.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/profiler.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/rrect_renderer.dart
+FILE: ../../../flutter/lib/web_ui/lib/src/engine/safe_browser_api.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/semantics.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/semantics/accessibility.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/semantics/checkable.dart
@@ -620,7 +620,6 @@ FILE: ../../../flutter/lib/web_ui/lib/src/engine/ulps.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/util.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/validators.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/vector_math.dart
-FILE: ../../../flutter/lib/web_ui/lib/src/engine/web_experiments.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/engine/window.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/ui/annotations.dart
 FILE: ../../../flutter/lib/web_ui/lib/src/ui/canvas.dart