[Impeller] forgetting to set the sampler in a FragmentShader causes native crash #115027
Description
(lldb) 2022-11-09 14:53:33.938698-0800 Runner[8688:1088334] [VERBOSE-2:FlutterDarwinContextMetalImpeller.mm(26)] Using the Impeller rendering backend.
* thread #11, name = 'io.flutter.1.raster', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
frame #0: 0x0000000107d7a7bc Flutter`impeller::DisplayListDispatcher::setColorSource(flutter::DlColorSource const*) + 1444
Flutter`impeller::DisplayListDispatcher::setColorSource:
-> 0x107d7a7bc <+1444>: ldr x8, [x0]
0x107d7a7c0 <+1448>: ldr x8, [x8, #0x50]
0x107d7a7c4 <+1452>: blr x8
0x107d7a7c8 <+1456>: mov x22, x0
Target 0: (Runner) stopped.
Will take a look