[VOL-2235] Mocks and interfaces for rw-core

This update consists of mocks that are used by the rw-core
during unit testing.  It also includes interfaces used for unit
tests.

Change-Id: I20ca1455c358113c3aa897acc6355e0ddbc614b7
diff --git a/vendor/github.com/grpc-ecosystem/grpc-gateway/runtime/marshaler_registry.go b/vendor/github.com/grpc-ecosystem/grpc-gateway/runtime/marshaler_registry.go
new file mode 100644
index 0000000..5cc53ae
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/grpc-gateway/runtime/marshaler_registry.go
@@ -0,0 +1,91 @@
+package runtime
+
+import (
+	"errors"
+	"net/http"
+)
+
+// MIMEWildcard is the fallback MIME type used for requests which do not match
+// a registered MIME type.
+const MIMEWildcard = "*"
+
+var (
+	acceptHeader      = http.CanonicalHeaderKey("Accept")
+	contentTypeHeader = http.CanonicalHeaderKey("Content-Type")
+
+	defaultMarshaler = &JSONPb{OrigName: true}
+)
+
+// MarshalerForRequest returns the inbound/outbound marshalers for this request.
+// It checks the registry on the ServeMux for the MIME type set by the Content-Type header.
+// If it isn't set (or the request Content-Type is empty), checks for "*".
+// If there are multiple Content-Type headers set, choose the first one that it can
+// exactly match in the registry.
+// Otherwise, it follows the above logic for "*"/InboundMarshaler/OutboundMarshaler.
+func MarshalerForRequest(mux *ServeMux, r *http.Request) (inbound Marshaler, outbound Marshaler) {
+	for _, acceptVal := range r.Header[acceptHeader] {
+		if m, ok := mux.marshalers.mimeMap[acceptVal]; ok {
+			outbound = m
+			break
+		}
+	}
+
+	for _, contentTypeVal := range r.Header[contentTypeHeader] {
+		if m, ok := mux.marshalers.mimeMap[contentTypeVal]; ok {
+			inbound = m
+			break
+		}
+	}
+
+	if inbound == nil {
+		inbound = mux.marshalers.mimeMap[MIMEWildcard]
+	}
+	if outbound == nil {
+		outbound = inbound
+	}
+
+	return inbound, outbound
+}
+
+// marshalerRegistry is a mapping from MIME types to Marshalers.
+type marshalerRegistry struct {
+	mimeMap map[string]Marshaler
+}
+
+// add adds a marshaler for a case-sensitive MIME type string ("*" to match any
+// MIME type).
+func (m marshalerRegistry) add(mime string, marshaler Marshaler) error {
+	if len(mime) == 0 {
+		return errors.New("empty MIME type")
+	}
+
+	m.mimeMap[mime] = marshaler
+
+	return nil
+}
+
+// makeMarshalerMIMERegistry returns a new registry of marshalers.
+// It allows for a mapping of case-sensitive Content-Type MIME type string to runtime.Marshaler interfaces.
+//
+// For example, you could allow the client to specify the use of the runtime.JSONPb marshaler
+// with a "application/jsonpb" Content-Type and the use of the runtime.JSONBuiltin marshaler
+// with a "application/json" Content-Type.
+// "*" can be used to match any Content-Type.
+// This can be attached to a ServerMux with the marshaler option.
+func makeMarshalerMIMERegistry() marshalerRegistry {
+	return marshalerRegistry{
+		mimeMap: map[string]Marshaler{
+			MIMEWildcard: defaultMarshaler,
+		},
+	}
+}
+
+// WithMarshalerOption returns a ServeMuxOption which associates inbound and outbound
+// Marshalers to a MIME type in mux.
+func WithMarshalerOption(mime string, marshaler Marshaler) ServeMuxOption {
+	return func(mux *ServeMux) {
+		if err := mux.marshalers.add(mime, marshaler); err != nil {
+			panic(err)
+		}
+	}
+}