WebNN: Implement MLBuffer creation/destroy.

Introduces MLBuffer to the WebNN service. Since MLBuffer exists in the
 domain of the context, instead of a graph, a dedicated command
 recorder was needed to ensure future context operations
 (ie. readBuffer) get applied prior to graph operations.

* Defines handles to identify objects in the ML service.
* Defines MLBuffer interfaces.
* Implements buffer creation and destruction.

webmachinelearning/webnn#482

Bug: 1472888
Change-Id: I852eff452346a968812e9f248fbb0a4cfc917dbc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5173676
Reviewed-by: ningxin hu <[email protected]>
Reviewed-by: Reilly Grant <[email protected]>
Reviewed-by: Alex Gough <[email protected]>
Reviewed-by: Rafael Cintron <[email protected]>
Commit-Queue: Bryan Bernhart <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1270252}

webnn/conformance_tests/buffer.https.any.js

@@ -0,0 +1,12 @@
+// META: title=test WebNN API buffer operations
+// META: global=window,dedicatedworker
+// META: script=../resources/utils.js
+// META: timeout=long
+
+'use strict';
+
+// https://webmachinelearning.github.io/webnn/#api-mlbuffer
+
+testCreateWebNNBuffer("create", 4);
+
+testDestroyWebNNBuffer("destroyTwice");

webnn/conformance_tests/gpu/buffer.https.any.js

@@ -0,0 +1,12 @@
+// META: title=test WebNN API buffer operations
+// META: global=window,dedicatedworker
+// META: script=../../resources/utils.js
+// META: timeout=long
+
+'use strict';
+
+// https://webmachinelearning.github.io/webnn/#api-mlbuffer
+
+testCreateWebNNBuffer("create", 4, 'gpu');
+
+testDestroyWebNNBuffer("destroyTwice", 'gpu');

webnn/resources/utils.js

@@ -898,4 +898,60 @@ const toHalf = (value) => {
     * the exponent, which is OK. */
   bits += m & 1;
   return bits;
+};
+
+
+/**
+ * WebNN buffer creation.
+ * @param {MLContext} context - the context used to create the buffer.
+ * @param {Number} bufferSize - Size of the buffer to create, in bytes.
+ */
+const createBuffer = (context, bufferSize) => {
+  let buffer;
+  try {
+    buffer = context.createBuffer({size: bufferSize});
+    assert_equals(buffer.size, bufferSize);
+  } catch (e) {
+    assert_true(e instanceof DOMException);
+    assert_equals(e.name, "NotSupportedError");
+  }
+  return buffer;
+};
+
+/**
+ * WebNN destroy buffer twice test.
+ * @param {String} testName - The name of the test operation.
+ * @param {String} deviceType - The execution device type for this test.
+ */
+const testDestroyWebNNBuffer = (testName, deviceType = 'cpu') => {
+  let context;
+  let buffer;
+  promise_setup(async () => {
+    context = await navigator.ml.createContext({deviceType});
+    buffer = createBuffer(context, 4);
+  });
+  promise_test(async () => {
+    // MLBuffer is not supported for this deviceType.
+    if (buffer === undefined) {
+      return;
+    }
+    buffer.destroy();
+    buffer.destroy();
+  }, `${testName}`);
+};
+
+/**
+ * WebNN create buffer test.
+ * @param {String} testName - The name of the test operation.
+ * @param {Number} bufferSize - Size of the buffer to create, in bytes.
+ * @param {String} deviceType - The execution device type for this test.
+ */
+const testCreateWebNNBuffer = (testName, bufferSize, deviceType = 'cpu') => {
+  let context;
+  promise_setup(async () => {
+      context = await navigator.ml.createContext({deviceType});
+  });
+  promise_test(async () => {
+    createBuffer(context, bufferSize);
+  }, `${testName} / ${bufferSize}`);
 };