Add WebUSB bindings and client interface [part 2]

Source/modules/webusb/USB.cpp

Index: Source/modules/webusb/USB.cpp
diff --git a/Source/modules/webusb/USB.cpp b/Source/modules/webusb/USB.cpp
index c9ced1e1ab7470cbcad7730505d1e0f3fdaa25e6..03a0c68b1a82f715c06ebb147f961bc22781c87c 100644
--- a/Source/modules/webusb/USB.cpp
+++ b/Source/modules/webusb/USB.cpp
@@ -5,13 +5,71 @@
 #include "config.h"
 #include "modules/webusb/USB.h"
 
+#include "bindings/core/v8/CallbackPromiseAdapter.h"
+#include "bindings/core/v8/ScriptPromise.h"
+#include "bindings/core/v8/ScriptPromiseResolver.h"
+#include "core/dom/DOMException.h"
+#include "core/dom/Document.h"
+#include "core/dom/ExceptionCode.h"
+#include "modules/webusb/USBDevice.h"
 #include "modules/webusb/USBDeviceEnumerationOptions.h"
 #include "modules/webusb/USBDeviceFilter.h"
+#include "modules/webusb/USBError.h"
+#include "public/platform/Platform.h"
+#include "public/platform/WebVector.h"
 #include "public/platform/modules/webusb/WebUSBClient.h"
 #include "public/platform/modules/webusb/WebUSBDeviceEnumerationOptions.h"
 #include "public/platform/modules/webusb/WebUSBDeviceFilter.h"
+#include "public/platform/modules/webusb/WebUSBError.h"
 
 namespace blink {
+namespace {
+
+void convertDeviceEnumerationOptions(const USBDeviceEnumerationOptions& options, WebUSBDeviceEnumerationOptions* webOptions)
+{
+    ASSERT(options.hasFilters());
+    webOptions->filters = WebVector<WebUSBDeviceFilter>(options.filters().size());
+    for (size_t i = 0; i < options.filters().size(); ++i) {
+        const USBDeviceFilter& filter = options.filters()[i];
+        WebUSBDeviceFilter& webFilter = webOptions->filters[i];
+        webFilter.hasVendorID = filter.hasVendorId();
+        if (filter.hasVendorId())
+            webFilter.vendorID = filter.vendorId();
+        webFilter.hasProductID = filter.hasProductId();
+        if (filter.hasProductId())
+            webFilter.productID = filter.productId();
+        webFilter.hasClassCode = filter.hasClassCode();
+        if (filter.hasClassCode())
+            webFilter.classCode = filter.classCode();
+        webFilter.hasSubclassCode = filter.hasSubclassCode();
+        if (filter.hasSubclassCode())
+            webFilter.subclassCode = filter.subclassCode();
+        webFilter.hasProtocolCode = filter.hasProtocolCode();
+        if (filter.hasProtocolCode())
+            webFilter.protocolCode = filter.protocolCode();
+    }
+}
+
+// Allows using a CallbackPromiseAdapter with a WebVector to resolve the
+// getDevices() promise with a HeapVector owning USBDevices.
+class DeviceArray {
+    WTF_MAKE_NONCOPYABLE(DeviceArray);
+public:
+    using WebType = WebVector<WebUSBDevice*>;
+
+    static HeapVector<Member<USBDevice>> take(ScriptPromiseResolver*, PassOwnPtr<WebType> webDevices)
+    {
+        HeapVector<Member<USBDevice>> devices;
+        for (const auto webDevice : *webDevices)
+            devices.append(USBDevice::create(adoptPtr(webDevice)));
+        return devices;
+    }
+
+private:
+    DeviceArray() = delete;
+};
+
+} // namespace
 
 USB::USB(LocalFrame& frame)
     : m_controller(USBController::from(frame))
@@ -20,8 +78,22 @@ USB::USB(LocalFrame& frame)
 
 ScriptPromise USB::getDevices(ScriptState* scriptState, const USBDeviceEnumerationOptions& options)
 {
+    WebUSBClient* client = m_controller->client();
+    if (!client)
+        return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(NotSupportedError));
+
+    RefPtrWillBeRawPtr<ScriptPromiseResolver> resolver = ScriptPromiseResolver::create(scriptState);
+    ScriptPromise promise = resolver->promise();
+
+    WebUSBDeviceEnumerationOptions webOptions;
+    convertDeviceEnumerationOptions(options, &webOptions);
+
+    // TODO(rockot): Re-enable this after CPA changes land.
+    // That's https://codereview.chromium.org/1240763002/ and dependent patches.
+    // client->getDevices(webOptions, new CallbackPromiseAdapter<DeviceArray, USBError>(resolver));
     ASSERT_NOT_REACHED();
-    return ScriptPromise();
+
+    return promise;
 }
 
 DEFINE_TRACE(USB)