[serial] Support filtering ports by USB vendor and product IDs

This change implements support for filtering serial ports based on a USB
vendor and product ID. The naming of the filter properties comes from
the Serial API polyfill library where I felt it was important to be
specific that this filter will only apply to USB devices and so also
implies that the device being requested by the page will be a USB
device.

This is useful for applications which are targeting a particular model
of serial device that is known to be connected over USB and advertises
a recognizable vendor ID/product ID pair.

Bug: 884928
Change-Id: Ie6a2674911c449ed48d58ea82175fe03bc14c572
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1994262Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Ovidio de Jesús Ruiz-Henríquez <odejesush@chromium.org>
Commit-Queue: Reilly Grant <reillyg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#730218}

third_party/blink/renderer/modules/modules_idl_files.gni

@@ -912,6 +912,7 @@ if (!is_android) {
                       "serial/serial_input_signals.idl",
                       "serial/serial_options.idl",
                       "serial/serial_output_signals.idl",
+                      "serial/serial_port_filter.idl",
                       "serial/serial_port_request_options.idl",
                     ],
                     "abspath")

third_party/blink/renderer/modules/serial/serial.cc

@@ -18,6 +18,8 @@
 #include "third_party/blink/renderer/core/frame/local_frame.h"
 #include "third_party/blink/renderer/modules/event_target_modules_names.h"
 #include "third_party/blink/renderer/modules/serial/serial_port.h"
+#include "third_party/blink/renderer/modules/serial/serial_port_filter.h"
+#include "third_party/blink/renderer/modules/serial/serial_port_request_options.h"
 #include "third_party/blink/renderer/platform/heap/heap.h"
 
 namespace blink {
@@ -102,11 +104,40 @@ ScriptPromise Serial::requestPort(ScriptState* script_state,
     return ScriptPromise();
   }
 
+  Vector<mojom::blink::SerialPortFilterPtr> filters;
+  if (options && options->hasFilters()) {
+    for (const auto& filter : options->filters()) {
+      auto mojo_filter = mojom::blink::SerialPortFilter::New();
+
+      mojo_filter->has_vendor_id = filter->hasUsbVendorId();
+      if (mojo_filter->has_vendor_id) {
+        mojo_filter->vendor_id = filter->usbVendorId();
+      } else {
+        exception_state.ThrowTypeError(
+            "A filter must provide a property to filter by.");
+        return ScriptPromise();
+      }
+
+      mojo_filter->has_product_id = filter->hasUsbProductId();
+      if (mojo_filter->has_product_id) {
+        if (!mojo_filter->has_vendor_id) {
+          exception_state.ThrowTypeError(
+              "A filter containing a usbProductId must also specify a "
+              "usbVendorId.");
+          return ScriptPromise();
+        }
+        mojo_filter->product_id = filter->usbProductId();
+      }
+
+      filters.push_back(std::move(mojo_filter));
+    }
+  }
+
   auto* resolver = MakeGarbageCollected<ScriptPromiseResolver>(script_state);
   request_port_promises_.insert(resolver);
 
   EnsureServiceConnection();
-  service_->RequestPort(Vector<mojom::blink::SerialPortFilterPtr>(),
+  service_->RequestPort(std::move(filters),
                         WTF::Bind(&Serial::OnRequestPort, WrapPersistent(this),
                                   WrapPersistent(resolver)));
 

third_party/blink/renderer/modules/serial/serial_port_filter.idl

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// https://wicg.github.io/serial
+
+dictionary SerialPortFilter {
+  unsigned short usbVendorId;
+  unsigned short usbProductId;
+};

third_party/blink/renderer/modules/serial/serial_port_request_options.idl

@@ -5,4 +5,5 @@
 // https://wicg.github.io/serial
 
 dictionary SerialPortRequestOptions {
+  sequence<SerialPortFilter> filters;
 };

third_party/blink/web_tests/serial/serial_requestPort.html

@@ -55,5 +55,34 @@ serial_test(async (t, fake) => {
   assert_true(firstPort === secondPort);
 }, 'requestPort() returns the same port object every time');
 
+serial_test(async (t, fake) => {
+  let guid = fake.addPort();
+  fake.setSelectedPort(guid);
+
+  await trustedClick();
+  let port = await navigator.serial.requestPort({ filters: [] });
+  assert_true(port instanceof SerialPort);
+}, 'An empty list of filters is valid');
+
+serial_test(async (t, fake) => {
+  let guid = fake.addPort();
+  fake.setSelectedPort(guid);
+
+  await trustedClick();
+  return promise_rejects(t, new TypeError(), navigator.serial.requestPort({
+    filters: [{}],
+  }));
+}, 'An empty filter is not valid');
+
+serial_test(async (t, fake) => {
+  let guid = fake.addPort();
+  fake.setSelectedPort(guid);
+
+  await trustedClick();
+  return promise_rejects(t, new TypeError(), navigator.serial.requestPort({
+    filters: [{ usbProductId: 0x0001 }],
+  }));
+}, 'requestPort() requires a USB vendor ID if a product ID specified');
+
 </script>
 </body>