Kotlin: Remove unused code paths in type conversion.

Following changes in API, type design, and tree-shaking used to
remove unused converters, these code paths are no longer needed.

A shorter codebase is easier to understand and work on.

Bug: b/429149631
Test: ./gradlew connectedAndroidTest
Change-Id: Idea5f0302f1f7938a32448b4cfdfaa177eeb2ba6
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/277295
Commit-Queue: Jim Blackler <jimblackler@google.com>
Reviewed-by: Ria Singhla <rsinghla@google.com>

generator/templates/art/api_jni_types.cpp

diff --git a/generator/templates/art/api_jni_types.cpp b/generator/templates/art/api_jni_types.cpp
index 6c16279..fb272a1 100644
--- a/generator/templates/art/api_jni_types.cpp
+++ b/generator/templates/art/api_jni_types.cpp
@@ -77,18 +77,6 @@
     {%- endif -%}
 {% endmacro %}
 
-{% macro convert_array_element_to_kotlin(input, output, size, member) %}
-    {%- if member.type.category in ['bitmask', 'enum'] -%}
-        //* Kotlin value classes do not get inlined in arrays, so the creation method is different.
-        jclass clz = classes->{{ member.type.name.camelCase() }};
-        jmethodID init = env->GetMethodID(clz, "<init>", "(I)V");
-        jobject {{ output }} = env->NewObject(clz, init, static_cast<jint>({{ input }}));
-    {%- else -%}
-        //* Declares an instance of 'output'
-        {{ convert_to_kotlin(input, output, size, member) }}
-    {%- endif -%}
-{% endmacro %}
-
 {% macro convert_to_kotlin(input, output, size, member) %}
     {% if size is string %}
         {% if member.type.name.get() in ['void const *', 'void *'] %}
@@ -98,7 +86,7 @@
             jobjectArray {{ output }} = env->NewObjectArray(
                     {{ size }}, classes->{{ member.type.name.camelCase() }}, 0);
             for (int idx = 0; idx != {{ size }}; idx++) {
-                {{ convert_array_element_to_kotlin(input + '[idx]', 'element', None, {'type': member.type})  | indent(4) }}
+                {{ convert_to_kotlin(input + '[idx]', 'element', None, {'type': member.type})  | indent(4) }}
                 env->SetObjectArrayElement({{ output }}, idx, element);
             }
         {% elif member.type.category in ['bitmask', 'enum'] or member.type.name.get() in ['int', 'int32_t', 'uint32_t'] %}
@@ -116,15 +104,10 @@
         }
     {% elif member.type.category == 'structure' %}
         jobject {{ output }} = ToKotlin(env, {{ '&' if member.annotation not in ['*', 'const*'] }}{{ input }});
-    {% elif member.type.name.get() == 'void *' %}
-        jlong {{ output }} = reinterpret_cast<jlong>({{ input }});
     {% elif member.type.category in ['bitmask', 'enum', 'native'] %}
         //* We use Kotlin value classes for bitmask and enum, and they get inlined as lone values.
         {{ to_jni_type(member.type) }} {{ output }} = static_cast<{{ to_jni_type(member.type) }}>({{ input }});
-    {% elif member.type.category in ['callback function', 'function pointer'] %}
-        jobject {{ output }} = nullptr;
-        dawn::WarningLog() << "while converting {{ as_cType(member.type.name) }}: Native callbacks cannot be converted to Kotlin";
     {% elif member.type.category != 'kotlin type' %}
-        {{ unreachable_code() }}
+        {{ unreachable_code('Unsupported type: ' + member.type.name.get()) }}
     {% endif %}
 {% endmacro %}

generator/templates/art/api_kotlin_types.kt

diff --git a/generator/templates/art/api_kotlin_types.kt b/generator/templates/art/api_kotlin_types.kt
index 1c3c9aa..07d7839 100644
--- a/generator/templates/art/api_kotlin_types.kt
+++ b/generator/templates/art/api_kotlin_types.kt
@@ -29,9 +29,7 @@
     {%- set type = arg.type %}
     {%- set optional = arg.optional and not strip_optional %}
     {%- set default_value = arg.default_value %}
-    {%- if arg == None -%}
-        Unit
-    {%- elif type.category == 'kotlin type' -%}
+    {%- if type.category == 'kotlin type' -%}
         {{ type.name.get() }}  {#- The name *is* the type #}
     {%- elif arg.type.name.get() == 'string view' -%}
         String{{ '?' if optional }}