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-increment-global-counter-loop-function/0-opt.spvasm.expected.wgsl

@@ -0,0 +1,93 @@
+type Arr = [[stride(16)]] array<i32, 4>;
+
+[[block]]
+struct buf0 {
+  x_GLF_uniform_int_values : Arr;
+};
+
+var<private> x_GLF_global_loop_count : i32;
+
+[[group(0), binding(0)]] var<uniform> x_7 : buf0;
+
+var<private> x_GLF_color : vec4<f32>;
+
+fn func_() {
+  var x_66_phi : i32;
+  let x_62 : i32 = x_7.x_GLF_uniform_int_values[1];
+  let x_64 : i32 = x_7.x_GLF_uniform_int_values[0];
+  x_66_phi = x_64;
+  loop {
+    var x_67 : i32;
+    let x_66 : i32 = x_66_phi;
+    let x_70 : i32 = x_7.x_GLF_uniform_int_values[3];
+    if ((x_66 < x_70)) {
+    } else {
+      break;
+    }
+
+    continuing {
+      let x_73 : i32 = x_GLF_global_loop_count;
+      x_GLF_global_loop_count = (x_73 + 1);
+      x_67 = (x_66 + 1);
+      x_66_phi = x_67;
+    }
+  }
+  if ((x_62 < x_62)) {
+    return;
+  }
+  return;
+}
+
+fn main_1() {
+  x_GLF_global_loop_count = 0;
+  loop {
+    let x_28 : i32 = x_GLF_global_loop_count;
+    if ((x_28 < 10)) {
+    } else {
+      break;
+    }
+
+    continuing {
+      let x_32 : i32 = x_GLF_global_loop_count;
+      x_GLF_global_loop_count = (x_32 + 1);
+      func_();
+    }
+  }
+  loop {
+    let x_36 : i32 = x_GLF_global_loop_count;
+    if ((x_36 < 10)) {
+    } else {
+      break;
+    }
+
+    continuing {
+      let x_40 : i32 = x_GLF_global_loop_count;
+      x_GLF_global_loop_count = (x_40 + 1);
+    }
+  }
+  let x_42 : i32 = x_GLF_global_loop_count;
+  let x_44 : i32 = x_7.x_GLF_uniform_int_values[2];
+  if ((x_42 == x_44)) {
+    let x_50 : i32 = x_7.x_GLF_uniform_int_values[1];
+    let x_51 : f32 = f32(x_50);
+    let x_53 : i32 = x_7.x_GLF_uniform_int_values[0];
+    let x_54 : f32 = f32(x_53);
+    x_GLF_color = vec4<f32>(x_51, x_54, x_54, x_51);
+  } else {
+    let x_57 : i32 = x_7.x_GLF_uniform_int_values[0];
+    let x_58 : f32 = f32(x_57);
+    x_GLF_color = vec4<f32>(x_58, x_58, x_58, x_58);
+  }
+  return;
+}
+
+struct main_out {
+  [[location(0)]]
+  x_GLF_color_1 : vec4<f32>;
+};
+
+[[stage(fragment)]]
+fn main() -> main_out {
+  main_1();
+  return main_out(x_GLF_color);
+}