Remove private headers from modulemaps generated by objc_ targets

--
MOS_MIGRATED_REVID=140498934

src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java b/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
index efa6b1d..3722572 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
@@ -452,15 +452,14 @@
       Optional<CompilationArtifacts> compilationArtifacts) {
     // TODO(bazel-team): Include textual headers in the module map when Xcode 6 support is
     // dropped.
+    // TODO(b/32225593): Include private headers in the module map.
     Iterable<Artifact> publicHeaders = attributes.hdrs();
-    Iterable<Artifact> privateHeaders = ImmutableList.of();
     if (compilationArtifacts.isPresent()) {
       CompilationArtifacts artifacts = compilationArtifacts.get();
       publicHeaders = Iterables.concat(publicHeaders, artifacts.getAdditionalHdrs());
-      privateHeaders = Iterables.concat(privateHeaders, artifacts.getPrivateHdrs());
     }
     CppModuleMap moduleMap = intermediateArtifacts.moduleMap();
-    registerGenerateModuleMapAction(moduleMap, publicHeaders, privateHeaders);
+    registerGenerateModuleMapAction(moduleMap, publicHeaders);
 
     return this;
   }
@@ -869,20 +868,17 @@
 
   /**
    * Registers an action that will generate a clang module map.
-   *
    * @param moduleMap the module map to generate
    * @param publicHeaders the headers that should be directly accessible by dependers
-   * @param privateHeaders the headers that should only be directly accessible by this module
    */
   private void registerGenerateModuleMapAction(
-      CppModuleMap moduleMap, Iterable<Artifact> publicHeaders, Iterable<Artifact> privateHeaders) {
+      CppModuleMap moduleMap, Iterable<Artifact> publicHeaders) {
     publicHeaders = Iterables.filter(publicHeaders, MODULE_MAP_HEADER);
-    privateHeaders = Iterables.filter(privateHeaders, MODULE_MAP_HEADER);
     ruleContext.registerAction(
         new CppModuleMapAction(
             ruleContext.getActionOwner(),
             moduleMap,
-            privateHeaders,
+            ImmutableList.<Artifact>of(),
             publicHeaders,
             attributes.moduleMapsForDirectDeps(),
             ImmutableList.<PathFragment>of(),

src/test/shell/bazel/apple/bazel_apple_test.sh

diff --git a/src/test/shell/bazel/apple/bazel_apple_test.sh b/src/test/shell/bazel/apple/bazel_apple_test.sh
index 4a9b245..1cabd28 100755
--- a/src/test/shell/bazel/apple/bazel_apple_test.sh
+++ b/src/test/shell/bazel/apple/bazel_apple_test.sh
@@ -809,4 +809,29 @@
   expect_log "ios/top.swift:1:1: error: expressions are not allowed at the top level"
 }
 
+# Test that it's possible to import Clang module of a target that contains private headers.
+function test_import_module_with_private_hdrs() {
+  rm -rf ios
+  mkdir -p ios
+  touch ios/Foo.h ios/Foo_Private.h
+
+cat >ios/main.swift <<EOF
+import ios_lib
+EOF
+
+cat >ios/BUILD <<EOF
+load("//tools/build_defs/apple:swift.bzl", "swift_library")
+
+objc_library(name = "lib",
+             srcs = ["Foo_Private.h"],
+             hdrs = ["Foo.h"])
+
+swift_library(name = "swiftmodule",
+              srcs = ["main.swift"],
+              deps = [":lib"])
+EOF
+  bazel build --verbose_failures --xcode_version=$XCODE_VERSION \
+      //ios:swiftmodule >$TEST_log 2>&1 || fail "should build"
+}
+
 run_suite "apple_tests"