Add field-initializing constructors to generated mojo structs.

cc/ipc/struct_traits_unittest.cc

 // Copyright 2016 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.
 
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "cc/input/selection.h"
 #include "cc/ipc/copy_output_request_struct_traits.h"
 #include "cc/ipc/traits_test_service.mojom.h"
 #include "cc/output/copy_output_result.h"
@@ skipping 30 matching lines @@
     callback.Run(b);
   }
 
   void EchoCompositorFrame(
       CompositorFrame c,
       const EchoCompositorFrameCallback& callback) override {
     callback.Run(std::move(c));
   }
 
   void EchoCompositorFrameMetadata(
-      const CompositorFrameMetadata& c,
+      CompositorFrameMetadata c,
       const EchoCompositorFrameMetadataCallback& callback) override {
-    callback.Run(c);
+    callback.Run(std::move(c));
   }
 
   void EchoCopyOutputRequest(
       std::unique_ptr<CopyOutputRequest> c,
       const EchoCopyOutputRequestCallback& callback) override {
     callback.Run(std::move(c));
   }
 
   void EchoCopyOutputResult(
       std::unique_ptr<CopyOutputResult> c,
@@ skipping 286 matching lines @@
   input.top_controls_shown_ratio = top_bar_shown_ratio;
   input.bottom_controls_height = bottom_bar_height;
   input.bottom_controls_shown_ratio = bottom_bar_shown_ratio;
   input.root_background_color = root_background_color;
   input.selection = selection;
   input.latency_info = latency_infos;
   input.referenced_surfaces = referenced_surfaces;
 
   mojom::TraitsTestServicePtr proxy = GetTraitsTestProxy();
   CompositorFrameMetadata output;
-  proxy->EchoCompositorFrameMetadata(input, &output);
+  proxy->EchoCompositorFrameMetadata(std::move(input), &output);
   EXPECT_EQ(device_scale_factor, output.device_scale_factor);
   EXPECT_EQ(root_scroll_offset, output.root_scroll_offset);
   EXPECT_EQ(page_scale_factor, output.page_scale_factor);
   EXPECT_EQ(scrollable_viewport_size, output.scrollable_viewport_size);
   EXPECT_EQ(root_layer_size, output.root_layer_size);
   EXPECT_EQ(min_page_scale_factor, output.min_page_scale_factor);
   EXPECT_EQ(max_page_scale_factor, output.max_page_scale_factor);
   EXPECT_EQ(root_overflow_x_hidden, output.root_overflow_x_hidden);
   EXPECT_EQ(root_overflow_y_hidden, output.root_overflow_y_hidden);
   EXPECT_EQ(may_contain_video, output.may_contain_video);
@@ skipping 815 matching lines @@
   EXPECT_EQ(u_plane_resource_id, out_quad->u_plane_resource_id());
   EXPECT_EQ(v_plane_resource_id, out_quad->v_plane_resource_id());
   EXPECT_EQ(a_plane_resource_id, out_quad->a_plane_resource_id());
   EXPECT_EQ(color_space, out_quad->color_space);
   EXPECT_EQ(resource_offset, out_quad->resource_offset);
   EXPECT_EQ(resource_multiplier, out_quad->resource_multiplier);
   EXPECT_EQ(bits_per_channel, out_quad->bits_per_channel);
 }
 
 }  // namespace cc