website: revised documentation for Compute Shared VPC resources (#725)

The documentation pages for these two resources were previously a little
muddled, with the argument references swapped and a non-working example
for the host project.

website/docs/r/compute_shared_vpc_host_project.html.markdown

@@ -3,40 +3,42 @@ layout: "google"
 page_title: "Google: google_compute_shared_vpc_host_project"
 sidebar_current: "docs-google-compute-shared-vpc-host-project"
 description: |-
- Allows enabling and disabling Shared VPC for the host Google Cloud Platform project.
+ Enables the Google Compute Engine Shared VPC feature for a project, assigning it as a host project.
 ---
 
-# google\_compute\_shared\_vpc\_host\_project
+# google_compute_shared_vpc_host_project
 
-Allows enabling and disabling Shared VPC for the host Google Cloud Platform project. For more information see
-[the official documentation](https://cloud.google.com/compute/docs/shared-vpc)
-and
-[API](https://cloud.google.com/compute/docs/reference/latest/projects).
+Enables the Google Compute Engine
+[Shared VPC](https://cloud.google.com/compute/docs/shared-vpc)
+feature for a project, assigning it as a Shared VPC host project.
+
+For more information, see,
+[the Project API documentation](https://cloud.google.com/compute/docs/reference/latest/projects),
+where the Shared VPC feature is referred to by its former name "XPN".
 
 ## Example Usage
 
 ```hcl
+# A host project provides network resources to associated service projects.
 resource "google_compute_shared_vpc_host_project" "host" {
-  project = "your-host-project-id"
+  project = "host-project-id"
 }
 
+# A service project gains access to network resources provided by its
+# associated host project.
 resource "google_compute_shared_vpc_service_project" "service1" {
-  project    = "your-service-project-id-1"
-  // The host project must enable shared VPC first
-  depends_on = ["google_compute_shared_vpc_host_project.host"]
+  host_project    = "${google_compute_shared_vpc_host_project.host.project}"
+  service_project = "service-project-id-1"
 }
-
 resource "google_compute_shared_vpc_service_project" "service2" {
-  project    = "your-service-project-id-2"
-  // The host project must enable shared VPC first
-  depends_on = ["google_compute_shared_vpc_host_project.host"]
+  host_project    = "${google_compute_shared_vpc_host_project.host.project}"
+  service_project = "service-project-id-2"
 }
 ```
 
 ## Argument Reference
 
-The following arguments are supported:
+The following arguments are expected:
 
-* `host_project` - (Required) The host project ID.
+* `project` - (Required) The ID of the project that will serve as a Shared VPC host project
 
-* `service_project` - (Required) The service project ID.

website/docs/r/compute_shared_vpc_service_project.html.markdown

@@ -3,26 +3,36 @@ layout: "google"
 page_title: "Google: google_compute_shared_vpc_service_project"
 sidebar_current: "docs-google-compute-shared-vpc-service-project"
 description: |-
- Allows enabling and disabling Shared VPC for a service Google Cloud Platform project.
+ Enables the Google Compute Engine Shared VPC feature for a project, assigning it as a service project.
 ---
 
-# google\_compute\_shared\_vpc\_service\_project
+# google_compute_shared_vpc_service_project
 
-Allows enabling and disabling Shared VPC for a service Google Cloud Platform project. For more information see
-[the official documentation](https://cloud.google.com/compute/docs/shared-vpc)
-and
-[API](https://cloud.google.com/compute/docs/reference/latest/projects).
+Enables the Google Compute Engine
+[Shared VPC](https://cloud.google.com/compute/docs/shared-vpc)
+feature for a project, assigning it as a Shared VPC service project associated
+with a given host project.
+
+For more information, see,
+[the Project API documentation](https://cloud.google.com/compute/docs/reference/latest/projects),
+where the Shared VPC feature is referred to by its former name "XPN".
 
 ## Example Usage
 
 ```hcl
-resource "google_compute_shared_vpc_host_project" "host" {
-  project     = "your-project-id"
+resource "google_compute_shared_vpc_service_project" "service1" {
+  host_project    = "host-project-id"
+  service_project = "service-project-id-1"
 }
 ```
 
+For a complete Shared VPC example with both host and service projects, see
+[`google_compute_shared_vpc_host_project`](/docs/providers/google/r/compute_shared_vpc_host_project.html).
+
 ## Argument Reference
 
-The following arguments are supported:
+The following arguments are expected:
+
+* `host_project` - (Required) The ID of a host project to associate.
 
-* `project` - (Required) The host project ID.
+* `service_project` - (Required) The ID of the project that will serve as a Shared VPC service project.