Add tests derived from VK-GL-CTS

This adds SPIR-V assembly and WGSL tests derived from VK-GL-CTS commit
571256871c2e2f03995373e1e4a02958d8cd8cf5. The following procedure was
followed:

- Those .amber files in VK-GL-CTS wholly owned by Google were
  identified

- All GLSL and SPIR-V shaders were extracted from the Amber files and
  converted into SPIR-V binaries

- The compact-ids pass of spirv-opt was applied to each binary

- Duplicate binaries were removed

- spirv-opt -O was used to obtain an optimized version of each remaining
  binary, with duplicates discarded

- Binaries that failed validation using spirv-val with target
  environment SPIR-V 1.3 were discarded

- Those binaries that tint could not successfully convert into WGSL were
  put aside for further investigation

- SPIR-V assembly versions of the remaining binaries are included in
  this CL

- test-runner with -generate-expected and -generate-skip was used to
  generate expected .spvasm, .msl, .hlsl and .wgsl outputs for these
  SPIR-V assembly tests

- Each successfully-generated .expected.wgsl is included in this CL
  again, as a WGLSL test

- test-runner with -generate-expected and -generate-skip was used again,
  to generate expected outputs for these WGSL tests

Change-Id: Ibe9baf2729cf97e0b633db9a426f53362a5de540
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/58842
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>

test/vk-gl-cts/graphicsfuzz/cov-for-array-initializing-modulo/0-opt.spvasm.expected.hlsl

@@ -0,0 +1,50 @@
+cbuffer cbuffer_x_6 : register(b0, space0) {
+  uint4 x_6[4];
+};
+static float4 x_GLF_color = float4(0.0f, 0.0f, 0.0f, 0.0f);
+
+void main_1() {
+  int i = 0;
+  int a[2] = (int[2])0;
+  const int x_32 = asint(x_6[2].x);
+  i = x_32;
+  while (true) {
+    const int x_37 = i;
+    const uint scalar_offset = ((16u * uint(0))) / 4;
+    const int x_39 = asint(x_6[scalar_offset / 4][scalar_offset % 4]);
+    if ((x_37 < x_39)) {
+    } else {
+      break;
+    }
+    const int x_43 = asint(x_6[1].x);
+    const int x_44 = i;
+    const int x_46 = asint(x_6[3].x);
+    const int tint_symbol_3[2] = {x_43, (int2(x_44, x_44) % int2(3, x_46)).y};
+    a = tint_symbol_3;
+    {
+      i = (i + 1);
+    }
+  }
+  const int x_55 = asint(x_6[2].x);
+  const int x_57 = a[x_55];
+  const int x_60 = asint(x_6[1].x);
+  const int x_63 = asint(x_6[1].x);
+  const int x_66 = asint(x_6[2].x);
+  const int x_68 = a[x_66];
+  x_GLF_color = float4(float(x_57), float(x_60), float(x_63), float(x_68));
+  return;
+}
+
+struct main_out {
+  float4 x_GLF_color_1;
+};
+struct tint_symbol {
+  float4 x_GLF_color_1 : SV_Target0;
+};
+
+tint_symbol main() {
+  main_1();
+  const main_out tint_symbol_1 = {x_GLF_color};
+  const tint_symbol tint_symbol_4 = {tint_symbol_1.x_GLF_color_1};
+  return tint_symbol_4;
+}