alts: add grpclb runtime

alts/BUILD.bazel

@@ -29,6 +29,7 @@ java_library(
         "src/main/java/io/grpc/alts/*.java",
     ]),
     visibility = ["//visibility:public"],
+    runtime_deps = ["//grpclb"],
     deps = [
         ":alts_internal",
         ":handshaker_java_grpc",

alts/build.gradle

@@ -22,6 +22,7 @@ dependencies {
             project(':grpc-stub'),
             libraries.lang,
             libraries.protobuf
+    runtime project(':grpc-grpclb')
     testCompile libraries.guava,
                 libraries.guava_testlib,
                 libraries.junit,