Revert "Remove unused protobuf from backend.native"

This reverts commit 7a526a85

kotlin-native/backend.native/build.gradle

@@ -9,8 +9,14 @@ import org.jetbrains.gradle.plugins.tools.*
 buildscript {
     apply from: "../../kotlin-native/gradle/kotlinGradlePlugin.gradle"
     apply plugin: 'project-report'
+
+    dependencies {
+        classpath "com.google.protobuf:protobuf-gradle-plugin:0.8.8"
+    }
 }
 
+String protobufVersion = '2.6.1'
+apply plugin: "com.google.protobuf"
 apply plugin: 'java'
 apply plugin: 'kotlin'
 apply plugin: org.jetbrains.kotlin.NativeInteropPlugin
@@ -18,6 +24,11 @@ apply plugin: "maven-publish"
 
 sourceSets {
     compiler {
+        proto.srcDir 'compiler/ir/backend.native/src/'
+        java {
+            srcDir 'compiler/ir/backend.native/src/'
+            srcDir 'build/renamed/source/proto/compiler/java'
+        }
         kotlin {
             srcDir 'compiler/ir/backend.native/src/'
             srcDir '../shared/src/main/kotlin'
@@ -29,11 +40,16 @@ sourceSets {
         resources.srcDir VersionGeneratorKt.kotlinNativeVersionResourceFile(project).parentFile.parent
     }
     cli_bc {
+        java.srcDir 'cli.bc/src'
         kotlin.srcDir 'cli.bc/src'
     }
 }
 
 compileCompilerKotlin {
+    dependsOn('renamePackage')
+    // The protobuf plugin specifies this dependency for java by itself,
+    // but not for Kotlin.
+    dependsOn('generateCompilerProto')
     kotlinOptions.jvmTarget = "1.8"
     kotlinOptions.allWarningsAsErrors=true
     kotlinOptions.freeCompilerArgs += ['-Xopt-in=kotlin.RequiresOptIn', '-Xopt-in=org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI', '-Xskip-prerelease-check']
@@ -43,6 +59,27 @@ compileCli_bcKotlin {
     kotlinOptions.freeCompilerArgs += ['-Xskip-prerelease-check']
 }
 
+compileCompilerJava {
+    dependsOn('renamePackage')
+}
+
+task copyGenerated(type: Copy) {
+    dependsOn('generateCompilerProto')
+    from 'build/generated/source/proto/compiler/java'
+    into 'build/renamed/source/proto/compiler/java'
+    filter { line -> line.replaceAll("com.google.protobuf", "org.jetbrains.kotlin.protobuf") }
+    outputs.dir('build/renamed')
+}
+
+task deleteGenerated(type: Delete) {
+    dependsOn('copyGenerated')
+    delete 'build/generated/source/proto/compiler/java'
+}
+
+task renamePackage {
+    dependsOn('copyGenerated', 'deleteGenerated')
+}
+
 kotlinNativeInterop {
     llvm {
 
@@ -121,6 +158,8 @@ dependencies {
 
     compilerCompile project(":kotlin-native:utilities:basic-utils")
 
+    compilerCompile "com.google.protobuf:protobuf-java:${protobufVersion}"
+
     compilerCompile project(kotlinCompilerModule)
     compilerCompile project(":native:kotlin-native-utils")
     compilerCompile project(":core:descriptors")
@@ -273,6 +312,19 @@ externalJars.each { arg ->
 task external_jars(type: Copy) {
     dependsOn externalJars.collect { "${it}Copy" }
     dependsOn trove4jCopy
+
+    from configurations.compilerCompile {
+
+        include "protobuf-java-${protobufVersion}.jar"
+
+        into 'build/external_jars'
+    }
+}
+
+protobuf {
+    protoc {
+        artifact = "com.google.protobuf:protoc:${protobufVersion}"
+    }
 }
 
 task debugCompiler(type: JavaExec) {