Revert "Roll Dart to a5c11d7. (flutter#5259)" (flutter#5266)

This reverts commit 755dbee.

DEPS

@@ -31,7 +31,7 @@ vars = {
   # Dart is: https://github.com/dart-lang/sdk/blob/master/DEPS.
   # You can use //tools/dart/create_updated_flutter_deps.py to produce
   # updated revision list of existing dependencies.
-  'dart_revision': 'a5c11d7d0329432ca37e35bb249b20f60aa0aa31',
+  'dart_revision': '46ab040e589adc5200370dec7952ce5150850822',
 
   'dart_args_tag': '1.4.1',
   'dart_async_tag': '2.0.6',
@@ -126,7 +126,7 @@ deps = {
    Var('fuchsia_git') + '/garnet' + '@' + 'b7492b5f34e32248b164eb48ae8e67995aebda67',
 
   'src/topaz':
-   Var('fuchsia_git') + '/topaz' + '@' + '5fa651cf9cc5f338379e34964ff5dd70052f6237',
+   Var('fuchsia_git') + '/topaz' + '@' + 'e331f910c1003d154a4de6e1b5356f8d785fd6ec',
 
   'src/third_party/benchmark':
    Var('fuchsia_git') + '/third_party/benchmark' + '@' + '296537bc48d380adf21567c5d736ab79f5363d22',

content_handler/BUILD.gn

@@ -70,6 +70,7 @@ template("flutter_content_handler") {
 
     deps = [
              "//third_party/dart/runtime/bin:libdart_builtin",
+             "//third_party/dart/runtime/platform:libdart_platform",
              "//garnet/public/lib/app/cpp",
              "//garnet/public/lib/fonts/fidl",
              "//garnet/public/lib/fsl",
@@ -107,16 +108,10 @@ template("flutter_content_handler") {
 
 flutter_content_handler("aot") {
   output_name = "flutter_aot_runner"
-  extra_deps = [
-    "//third_party/dart/runtime:libdart_precompiled_runtime",
-    "//third_party/dart/runtime/platform:libdart_platform_precompiled_runtime",
-  ]
+  extra_deps = [ "//third_party/dart/runtime:libdart_precompiled_runtime" ]
 }
 
 flutter_content_handler("jit") {
   output_name = "flutter_jit_runner"
-  extra_deps = [
-    "//third_party/dart/runtime:libdart_jit",
-    "//third_party/dart/runtime/platform:libdart_platform_jit",
-  ]
+  extra_deps = [ "//third_party/dart/runtime:libdart_jit" ]
 }

runtime/dart_isolate.cc

@@ -541,10 +541,10 @@ Dart_Isolate DartIsolate::DartCreateAndStartServiceIsolate(
   // thread.
   service_isolate->ResetWeakPtrFactory();
 
-  const bool isolate_snapshot_is_dart_2 = Dart_IsDart2Snapshot(
-      vm->GetIsolateSnapshot()->GetData()->GetSnapshotPointer());
+  const bool isolate_snapshot_is_dart_2 =
+      Dart_IsDart2Snapshot(vm->GetIsolateSnapshot()->GetData()->GetSnapshotPointer());
   const bool is_preview_dart2 =
-      (vm->GetPlatformKernel().GetSize() > 0) || isolate_snapshot_is_dart_2;
+      vm->GetPlatformKernel() != nullptr || isolate_snapshot_is_dart_2;
   const bool running_from_sources =
       !DartVM::IsRunningPrecompiledCode() && !is_preview_dart2;
 
@@ -648,16 +648,14 @@ DartIsolate::CreateDartVMAndEmbedderObjectPair(
 
   // Create the Dart VM isolate and give it the embedder object as the baton.
   Dart_Isolate isolate =
-      (vm->GetPlatformKernel().GetSize() > 0)
-          ? Dart_CreateIsolateFromKernel(
-                advisory_script_uri,                   //
-                advisory_script_entrypoint,            //
-                vm->GetPlatformKernel().GetMapping(),  //
-                vm->GetPlatformKernel().GetSize(),     //
-                flags,                                 //
-                embedder_isolate.get(),                //
-                error                                  //
-                )
+      vm->GetPlatformKernel() != nullptr
+          ? Dart_CreateIsolateFromKernel(advisory_script_uri,         //
+                                         advisory_script_entrypoint,  //
+                                         vm->GetPlatformKernel(),     //
+                                         flags,                       //
+                                         embedder_isolate.get(),      //
+                                         error                        //
+                                         )
           : Dart_CreateIsolate(advisory_script_uri,         //
                                advisory_script_entrypoint,  //
                                embedder_isolate->GetIsolateSnapshot()

runtime/dart_vm.cc

@@ -278,6 +278,18 @@ DartVM::DartVM(const Settings& settings,
   FXL_DCHECK(isolate_snapshot_ && isolate_snapshot_->IsValid())
       << "Isolate snapshot must be valid.";
 
+  if (platform_kernel_mapping_->GetSize() > 0) {
+    // The platform kernel mapping lifetime is managed by this instance of the
+    // DartVM and hence will exceed that of the PlatformKernel. So provide an
+    // empty release callback.
+    Dart_ReleaseBufferCallback empty = [](auto arg) {};
+    platform_kernel_ = reinterpret_cast<PlatformKernel*>(Dart_ReadKernelBinary(
+        platform_kernel_mapping_->GetMapping(),  // buffer
+        platform_kernel_mapping_->GetSize(),     // buffer size
+        empty                                    // buffer deleter
+        ));
+  }
+
   {
     TRACE_EVENT0("flutter", "dart::bin::BootstrapDartIo");
     dart::bin::BootstrapDartIo();
@@ -328,11 +340,11 @@ DartVM::DartVM(const Settings& settings,
       Dart_IsDart2Snapshot(isolate_snapshot_->GetData()->GetSnapshotPointer());
 
   const bool is_preview_dart2 =
-      (platform_kernel_mapping_->GetSize() > 0) || isolate_snapshot_is_dart_2;
+      platform_kernel_ != nullptr || isolate_snapshot_is_dart_2;
 
   FXL_DLOG(INFO) << "Dart 2 " << (is_preview_dart2 ? "is" : "is NOT")
                  << " enabled. Platform kernel: "
-                 << static_cast<bool>(platform_kernel_mapping_->GetSize() > 0)
+                 << static_cast<bool>(platform_kernel_)
                  << " Isolate Snapshot is Dart 2: "
                  << isolate_snapshot_is_dart_2;
 
@@ -441,8 +453,8 @@ const Settings& DartVM::GetSettings() const {
   return settings_;
 }
 
-const fml::Mapping& DartVM::GetPlatformKernel() const {
-  return *platform_kernel_mapping_.get();
+DartVM::PlatformKernel* DartVM::GetPlatformKernel() const {
+  return platform_kernel_;
 }
 
 const DartSnapshot& DartVM::GetVMSnapshot() const {

runtime/dart_vm.h

@@ -25,6 +25,8 @@ namespace blink {
 
 class DartVM : public fxl::RefCountedThreadSafe<DartVM> {
  public:
+  class PlatformKernel;
+
   static fxl::RefPtr<DartVM> ForProcess(Settings settings);
 
   static fxl::RefPtr<DartVM> ForProcess(
@@ -38,7 +40,7 @@ class DartVM : public fxl::RefCountedThreadSafe<DartVM> {
 
   const Settings& GetSettings() const;
 
-  const fml::Mapping& GetPlatformKernel() const;
+  PlatformKernel* GetPlatformKernel() const;
 
   const DartSnapshot& GetVMSnapshot() const;
 
@@ -53,6 +55,7 @@ class DartVM : public fxl::RefCountedThreadSafe<DartVM> {
   const fxl::RefPtr<DartSnapshot> vm_snapshot_;
   const fxl::RefPtr<DartSnapshot> isolate_snapshot_;
   std::unique_ptr<fml::Mapping> platform_kernel_mapping_;
+  PlatformKernel* platform_kernel_ = nullptr;
   ServiceProtocol service_protocol_;
   fxl::WeakPtrFactory<DartVM> weak_factory_;
 

runtime/dart_vm_unittests.cc

@@ -15,7 +15,7 @@ TEST(DartVM, SimpleInitialization) {
   ASSERT_TRUE(vm);
   ASSERT_EQ(vm, DartVM::ForProcess(settings));
   ASSERT_FALSE(DartVM::IsRunningPrecompiledCode());
-  ASSERT_EQ(vm->GetPlatformKernel().GetSize(), 0u);
+  ASSERT_EQ(vm->GetPlatformKernel(), nullptr);
 }
 
 }  // namespace blink

shell/common/BUILD.gn

@@ -103,6 +103,7 @@ source_set("common") {
     "$flutter_root/third_party/txt",
     "//garnet/public/lib/fxl",
     "//third_party/dart/runtime:dart_api",
+    "//third_party/dart/runtime/platform:libdart_platform",
     "//third_party/rapidjson",
     "//third_party/skia",
     "//third_party/skia:gpu",

shell/testing/BUILD.gn

@@ -21,6 +21,8 @@ executable("testing") {
     "//garnet/public/lib/fxl",
     "//third_party/dart/runtime:libdart_jit",
     "//third_party/dart/runtime/bin:embedded_dart_io",
+    "//third_party/dart/runtime/bin:libdart_builtin",
+    "//third_party/dart/runtime/platform:libdart_platform",
     "//third_party/skia",
     "//topaz/lib/tonic",
   ]

travis/licenses_golden/licenses_third_party

@@ -1,4 +1,4 @@
-Signature: d07c068461636f8685c1a5d2cc38287c
+Signature: 44f02abeabaaa6e17185a06c9aa6ac8e
 
 UNUSED LICENSES: