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/scripts/microfactory.bash b/scripts/microfactory.bash
index 4bb6058..5e702e0 100644
--- a/scripts/microfactory.bash
+++ b/scripts/microfactory.bash
@@ -59,7 +59,7 @@
     BUILDDIR=$(getoutdir) \
       SRCDIR=${TOP} \
       BLUEPRINTDIR=${TOP}/build/blueprint \
-      EXTRA_ARGS="-pkg-path android/soong=${TOP}/build/soong -pkg-path github.com/golang/protobuf=${TOP}/external/golang-protobuf" \
+      EXTRA_ARGS="-pkg-path android/soong=${TOP}/build/soong -pkg-path google.golang.org/protobuf=${TOP}/external/golang-protobuf" \
       build_go $@
 }
 
diff --git a/scripts/setup_go_workspace_for_soong.sh b/scripts/setup_go_workspace_for_soong.sh
index 479d09c..434d2fb 100755
--- a/scripts/setup_go_workspace_for_soong.sh
+++ b/scripts/setup_go_workspace_for_soong.sh
@@ -346,7 +346,7 @@
   "${ANDROID_PATH}/build/blueprint|${OUTPUT_PATH}/src/github.com/google/blueprint"
   "${ANDROID_PATH}/build/soong|${OUTPUT_PATH}/src/android/soong"
   "${ANDROID_PATH}/art/build|${OUTPUT_PATH}/src/android/soong/art"
-  "${ANDROID_PATH}/external/golang-protobuf|${OUTPUT_PATH}/src/github.com/golang/protobuf"
+  "${ANDROID_PATH}/external/golang-protobuf|${OUTPUT_PATH}/src/google.golang.org/protobuf"
   "${ANDROID_PATH}/external/llvm/soong|${OUTPUT_PATH}/src/android/soong/llvm"
   "${ANDROID_PATH}/external/clang/soong|${OUTPUT_PATH}/src/android/soong/clang"
   "${ANDROID_PATH}/external/robolectric-shadows/soong|${OUTPUT_PATH}/src/android/soong/robolectric"