Fix compilation in Java 9

Tests still fail; at the very least because of missing Jetty ALPN. I
don't know why the dependency on javax.annotations is unnecessary in the
compiler tests and the example when using Maven.

Author: ejona86

benchmarks/build.gradle

@@ -34,6 +34,7 @@ dependencies {
             libraries.netty_tcnative,
             libraries.netty_epoll,
             libraries.math
+    compileOnly libraries.javax_annotation
 }
 
 compileJava {

build.gradle

@@ -185,6 +185,7 @@ subprojects {
                 errorprone: "com.google.errorprone:error_prone_annotations:2.0.19",
                 guava: "com.google.guava:guava:${guavaVersion}",
                 hpack: 'com.twitter:hpack:0.10.1',
+                javax_annotation: 'javax.annotation:javax.annotation-api:1.2',
                 jsr305: 'com.google.code.findbugs:jsr305:3.0.0',
                 oauth_client: 'com.google.auth:google-auth-library-oauth2-http:0.7.0',
                 google_api_protos: 'com.google.api.grpc:proto-google-common-protos:0.1.9',

examples/build.gradle

@@ -29,6 +29,7 @@ dependencies {
   compile "io.grpc:grpc-netty:${grpcVersion}"
   compile "io.grpc:grpc-protobuf:${grpcVersion}"
   compile "io.grpc:grpc-stub:${grpcVersion}"
+  compileOnly "javax.annotation:javax.annotation-api:1.2"
 
   testCompile "io.grpc:grpc-testing:${grpcVersion}"
   testCompile "junit:junit:4.12"

grpclb/build.gradle

@@ -14,6 +14,7 @@ dependencies {
             project(':grpc-protobuf'),
             project(':grpc-stub'),
             libraries.protobuf
+    compileOnly libraries.javax_annotation
     testCompile libraries.truth,
                 project(':grpc-core').sourceSets.test.output
 }

interop-testing/build.gradle

@@ -26,6 +26,7 @@ dependencies {
             libraries.netty_tcnative,
             libraries.oauth_client,
             libraries.truth
+    compileOnly libraries.javax_annotation
     runtime libraries.opencensus_impl
 }
 

okhttp/src/test/java/io/grpc/okhttp/OkHttpProtocolNegotiatorTest.java

@@ -53,6 +53,7 @@
 public class OkHttpProtocolNegotiatorTest {
   @Rule public final ExpectedException thrown = ExpectedException.none();
 
+  @SuppressWarnings("deprecation") // version became a string in Java 9
   private final Provider fakeSecurityProvider = new Provider("GmsCore_OpenSSL", 1.0, "info") {};
   private final SSLSocket sock = mock(SSLSocket.class);
   private final Platform platform = mock(Platform.class);

services/build.gradle

@@ -13,6 +13,7 @@ description = "gRPC: Services"
 dependencies {
     compile project(':grpc-protobuf'),
             project(':grpc-stub')
+    compileOnly libraries.javax_annotation
     testCompile project(':grpc-testing')
     signature "org.codehaus.mojo.signature:java16:1.1@signature"
 }

testing-proto/build.gradle

@@ -13,6 +13,7 @@ buildscript {
 dependencies {
     compile project(':grpc-protobuf'),
             project(':grpc-stub')
+    compileOnly libraries.javax_annotation
     testCompile libraries.opencensus_api,
                 libraries.truth
     testRuntime libraries.opencensus_impl