Make Kotlin API object constructors private.

This prevents direct instantiation of these objects from Java/Kotlin code, as they should only be created via the C++ API.

Convert Texture bad width unit test to integration test.

Bug: b/373607496
Change-Id: Iaf52b61815b0b84a0637656abe09c490b0713257
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/268195
Reviewed-by: Jim Blackler <jimblackler@google.com>
Commit-Queue: Tarun Saini <sainitarun@google.com>

generator/templates/art/api_kotlin_object.kt

diff --git a/generator/templates/art/api_kotlin_object.kt b/generator/templates/art/api_kotlin_object.kt
index 614f287..dbc8475 100644
--- a/generator/templates/art/api_kotlin_object.kt
+++ b/generator/templates/art/api_kotlin_object.kt
@@ -43,7 +43,7 @@
 {% if doc_str | trim %}
     {{ generate_simple_kdoc(doc_str) }}
 {% endif %}
-public class {{ kotlin_name(obj) }}(public val handle: Long): AutoCloseable {
+public class {{ kotlin_name(obj) }} private constructor(public val handle: Long): AutoCloseable {
     {% set all_method_info = object_info.methods if object_info else {} %}
     {% for method in obj.methods if include_method(obj, method) %}
         //* Generating KDocs

tools/android/webgpu/src/androidTest/java/androidx/webgpu/TextureTest.kt

diff --git a/tools/android/webgpu/src/androidTest/java/androidx/webgpu/TextureTest.kt b/tools/android/webgpu/src/androidTest/java/androidx/webgpu/TextureTest.kt
index 6cc9b2a..ed82d6d 100644
--- a/tools/android/webgpu/src/androidTest/java/androidx/webgpu/TextureTest.kt
+++ b/tools/android/webgpu/src/androidTest/java/androidx/webgpu/TextureTest.kt
@@ -1,8 +1,10 @@
 package androidx.webgpu
 
 import androidx.test.filters.SmallTest
+import androidx.webgpu.helper.DawnException
 import androidx.webgpu.helper.ValidationException
 import androidx.webgpu.helper.WebGpu
+import androidx.webgpu.helper.createBitmap
 import androidx.webgpu.helper.createWebGpu
 import kotlinx.coroutines.runBlocking
 import org.junit.After
@@ -119,4 +121,22 @@
       encoder.close()
     }
   }
+
+  /**
+   * Verifies that creating a bitmap from a texture with an invalid width fails.
+   */
+  @Test
+  fun createBitmap_withInvalidWidth_fails() {
+    val descriptor = TextureDescriptor(
+      size = Extent3D(width = 65, height = 16, depthOrArrayLayers = 1),
+      format = TextureFormat.RGBA8Unorm,
+      usage = TextureUsage.CopySrc
+    )
+    val texture = device.createTexture(descriptor)
+    assertThrows(DawnException::class.java) {
+      runBlocking {
+        texture.createBitmap(device)
+      }
+    }
+  }
 }
\ No newline at end of file

tools/android/webgpu/src/test/java/androidx/webgpu/TexturesTest.kt

diff --git a/tools/android/webgpu/src/test/java/androidx/webgpu/TexturesTest.kt b/tools/android/webgpu/src/test/java/androidx/webgpu/TexturesTest.kt
deleted file mode 100644
index edc9c1b..0000000
--- a/tools/android/webgpu/src/test/java/androidx/webgpu/TexturesTest.kt
+++ /dev/null
@@ -1,26 +0,0 @@
-package androidx.webgpu
-
-import androidx.webgpu.helper.DawnException
-import androidx.webgpu.helper.createBitmap
-import kotlin.test.assertFailsWith
-import kotlinx.coroutines.test.runTest
-import org.junit.Test
-import org.mockito.Mockito.doReturn
-import org.mockito.Mockito.spy
-import org.mockito.kotlin.mock
-import org.mockito.kotlin.whenever
-
-class TexturesTest {
-
-    @Test
-    @kotlinx.coroutines.ExperimentalCoroutinesApi
-    fun testBadWidthIsCaught() = runTest {
-        val mockDevice = mock<GPUDevice>()
-        val partialMockTexture = spy(GPUTexture(0))
-
-        doReturn(65).whenever(partialMockTexture).width
-        assertFailsWith<DawnException>{
-            partialMockTexture.createBitmap(mockDevice)
-        }
-    }
-}