GLSL: Don't use a typedef for array returns.

Covered by GlslGeneratorImplTest_Function.Emit_Function_WithArrayReturn

Bug: tint:1258
Change-Id: I181641ebe170ec359d9833e9022e6e70747fde9a
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/67240
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Stephen White <senorblanco@chromium.org>

src/writer/glsl/generator_impl.cc

@@ -1465,24 +1465,10 @@ bool GeneratorImpl::EmitFunction(const ast::Function* func) {
   {
     auto out = line();
     auto name = builder_.Symbols().NameFor(func->symbol);
-    // If the function returns an array, then we need to declare a typedef for
-    // this.
-    if (sem->ReturnType()->Is<sem::Array>()) {
-      auto typedef_name = UniqueIdentifier(name + "_ret");
-      auto pre = line();
-      pre << "typedef ";
-      if (!EmitTypeAndName(pre, sem->ReturnType(), ast::StorageClass::kNone,
-                           ast::Access::kReadWrite, typedef_name)) {
-        return false;
-      }
-      pre << ";";
-      out << typedef_name;
-    } else {
     if (!EmitType(out, sem->ReturnType(), ast::StorageClass::kNone,
                   ast::Access::kReadWrite, "")) {
       return false;
     }
-    }
 
     out << " " << name << "(";
 

src/writer/glsl/generator_impl_function_test.cc

@@ -999,8 +999,7 @@ TEST_F(GlslGeneratorImplTest_Function, Emit_Function_WithArrayReturn) {
   EXPECT_EQ(gen.result(), R"(#version 310 es
 precision mediump float;
 
-typedef float my_func_ret[5];
+float[5] my_func() {
-my_func_ret my_func() {
   return float[5](0.0f, 0.0f, 0.0f, 0.0f, 0.0f);
 }
 )");