Rfc410 prototype - #195336

…exture, and semantics extensions

…nternal headers (RFC 410.0000)

…r_info.h

…, and hybrid composition presubmit failures

…nup, macOS shutdown deadlock, and clang-tidy

- Open the parent directory with `fml::FilePermission::kRead` in `CallbackCache::SaveCacheToDisk()` so `OpenDirectory` on Windows shares read/write/delete access (`GetShareFlags(kRead)`) instead of failing with `ERROR_SHARING_VIOLATION` (`32`) when `ScopedTemporaryDirectory` holds an open directory handle.
- Clean up `custom_asset_resolver_.user_data` in `FlutterEmbedderNative` and invoke `custom_asset_resolvers[i]->destruction_callback` and `PlatformMessageReleaseResponseHandle`'s `data_callback` in `flutter_embedder_native_unittests.cc` to resolve LeakSanitizer failures on `Linux linux_unopt`.
- Use `std::recursive_mutex`, retain `shared_from_this()`, and copy `std::function` callbacks onto the stack in `PlatformViewEmbedder::EmbedderPlatformMessageHandler` and `PlatformViewEmbedder` so synchronous engine teardown inside a platform message callback (`FlutterEngineTest.ResponseAfterEngineDied`) does not self-deadlock or access destroyed state.
- Value-initialize `flutter::GPUMTLTextureInfo texture_info = {}` and pass `on_make_current` / `on_clear_current` by `const&` in `MakeRenderTargetFromBackingStoreImpeller` in `embedder.cc` to satisfy `mac_clang_tidy`.

… shuts down engine

…est.dart

… message response lifetime

…e, and merge UI/platform thread

…ToRgb565Row

# Conflicts:
#	engine/src/flutter/shell/platform/android/android_shell_holder.cc

…and support Vulkan validation layers

…in FlutterEngineGroup spawn

…ons, and cross-thread message dispatch

- Marshal EmbedderEngine::SendPlatformMessage onto the platform task runner via fml::TaskRunner::RunNowOrPostTask so background JNI callers do not dereference the UI-thread-bound Engine WeakPtr during teardown.
- Enable Impeller optional Vulkan device extensions (VK_EXT_image_compression_control, VK_EXT_image_compression_control_swapchain, VK_KHR_sampler_ycbcr_conversion, AHB/foreign queue) and chained feature structs in AndroidSurfaceControl::InitializeVulkan so root surface and SurfaceControl overlays use matching AFRC fixed-rate compression formats on Mali GPUs.
- Destroy cached C++ overlay surfaces (10000+) and controller overlay state when the root window is destroyed or detached, and guard PlatformViewsController2.createOverlaySurface() when flutterView or rootSurfaceControl is null.
- Drain expired platform fml::MessageLoop tasks in FlutterEmbedderNative::RunOnRasterThreadSynchronously while waiting on the raster latch to prevent AB-BA deadlocks with AndroidPlatformViewsController::PresentView.

# Conflicts:
#	engine/src/flutter/shell/platform/android/android_context_dynamic_impeller.cc
#	engine/src/flutter/shell/platform/android/android_context_vk_impeller.cc

- Fix clang-analyzer-core.StackAddressEscape in flutter_embedder_native_unittests.cc
  by storing FakeSpawnJniState and CrossThreadTestState::platform_task_executed by
  value in static test state instead of storing pointers to local stack variables.
- Fix Android NDK jni.h compilation in flutter_shell_native_unittests by deducing the
  JNIEnv::functions table type via decltype instead of hardcoding JNINativeInterface_.
- Reorder FlutterEmbedderNative private fields in flutter_embedder_native.h to match
  clang-analyzer-optin.performance.Padding optimal layout (2 padding bytes vs 34).
- Merge upstream b5879a3 and update AndroidTaskRunners thread affinity back to
  fml::CpuAffinity::kNotEfficiency.

… using synthetic test_env_