Adds unary double operations to ARM64, enables many tests.

tests/co19/co19-runtime.status

Index: tests/co19/co19-runtime.status
===================================================================
--- tests/co19/co19-runtime.status	(revision 35839)
+++ tests/co19/co19-runtime.status	(working copy)
@@ -87,5 +87,37 @@
 LayoutTests/fast/*: SkipByDesign # DOM not supported on VM.
 WebPlatformTest/*: SkipByDesign # dart:html not supported on VM.
 
+
 [ $compiler == none && $runtime == vm && $arch == simarm64 ]
-*: Skip
+# Flaky
+LibTest/isolate/ReceivePort/*: Skip
+# Timeout.
+LibTest/collection/ListMixin/ListMixin_class_A01_t01: Skip
+LibTest/collection/ListBase/ListBase_class_A01_t01: Skip
+LibTest/math/MutableRectangle/boundingBox_A01_t01: Skip
+# Passes, but should fail like other architectures?
+LibTest/core/int/operator_left_shift_A01_t02: Skip
+# Bugs
+LibTest/math/Rectangle/boundingBox_A01_t01: Skip  # Timeout, RuntimeError
+LibTest/core/Uri/encodeQueryComponent_A01_t02: RuntimeError
+LibTest/core/Uri/Uri_A06_t03: RuntimeError
+LibTest/math/Rectangle/Rectangle.fromPoints_A01_t01: RuntimeError
+Language/12_Expressions/01_Constants_A13_t06: Crash
+# Unimplemented features:
+LibTest/typed_data/Float32List/Float32List_A01_t02: Crash # Float -> Double.
+
+
+[ $compiler == none && $runtime == vm && $arch == simarm64 && $mode == debug]
+# Bug
+Language/12_Expressions/01_Constants_A13_t06: Crash
+LibTest/core/List/List_class_A01_t01: Crash
+
+
+[ $compiler == none && $runtime == vm && $arch == simarm64 && $checked ]
+# Bug
+LibTest/isolate/Isolate/spawn_A01_t02: Crash
+
+
+[ $compiler == none && $runtime == vm && $arch == simarm64 && $mode == release && $checked ]
+# Bug
+LibTest/collection/LinkedHashSet/LinkedHashSet_class_A01_t01: Crash