Upgrade to golang protobuf api v2

Major operations:
 * Fix the go_package entries to be consistent, as the new tool
   complains when it doesn't have a '/'.
 * Regenerate with the new protoc-gen-go tool.
 * github.com/golang/protobuf -> google.golang.org/protobuf
 * proto.[Un]MarshalText -> prototext.[Un]Marshal

Change-Id: Ie1147bd2457fafb66ba555461b3bf14f0561a25d
diff --git a/ui/status/log.go b/ui/status/log.go
index 4a08acb..14df346 100644
--- a/ui/status/log.go
+++ b/ui/status/log.go
@@ -23,11 +23,11 @@
 	"os"
 	"strings"
 
-	"github.com/golang/protobuf/proto"
+	"google.golang.org/protobuf/proto"
 
 	"android/soong/ui/logger"
-	"android/soong/ui/status/build_error_proto"
-	"android/soong/ui/status/build_progress_proto"
+	soong_build_error_proto "android/soong/ui/status/build_error_proto"
+	soong_build_progress_proto "android/soong/ui/status/build_progress_proto"
 )
 
 type verboseLog struct {