dawn_wire: Add support for injecting/reserving swapchains

This will help experiment using dawn_wire for remoting WebGPU to render
on the screen.

Bug: None
Change-Id: I9a60ff8c3889ec917f6fd56e4cbb1ffef639748d
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/47621
Auto-Submit: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Brandon Jones <bajones@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>

src/dawn_wire/client/Client.cpp

@@ -96,6 +96,18 @@ namespace dawn_wire { namespace client {
         return result;
     }
 
+    ReservedSwapChain Client::ReserveSwapChain(WGPUDevice device) {
+        auto* allocation = SwapChainAllocator().New(this);
+
+        ReservedSwapChain result;
+        result.swapchain = ToAPI(allocation->object.get());
+        result.id = allocation->object->id;
+        result.generation = allocation->generation;
+        result.deviceId = FromAPI(device)->id;
+        result.deviceGeneration = DeviceAllocator().GetGeneration(FromAPI(device)->id);
+        return result;
+    }
+
     ReservedDevice Client::ReserveDevice() {
         auto* allocation = DeviceAllocator().New(this);
 
@@ -110,6 +122,10 @@ namespace dawn_wire { namespace client {
         TextureAllocator().Free(FromAPI(reservation.texture));
     }
 
+    void Client::ReclaimSwapChainReservation(const ReservedSwapChain& reservation) {
+        SwapChainAllocator().Free(FromAPI(reservation.swapchain));
+    }
+
     void Client::ReclaimDeviceReservation(const ReservedDevice& reservation) {
         DeviceAllocator().Free(FromAPI(reservation.device));
     }