Experimental support for ios_framework rules

* Allows for building and linking to a framework in ios_application
* Currently only works for single arch builds
* Xcode generation produces correct target type, but is mostly untested

The implementation is very similar to that of objc_framework:

1) Build the ios_framework_binary as a dynamic library (-dynamiclib)

2) Symlink the library and public headers to a staging location, inside of "X.framework" bundle. Where X is the name under ios_framework_binary#framework_name

3) Pass the bundle content to ObjcCommon.addFrameworkImports, reusing the core of objc_framework rule implementation. This results in correctly set -F/-framework flags and allows clients to use the framework in a way they would use any SDK/3rd-party framework. It's allowed to import headers via #import <X/X.h> call.

4) Copy the binary and all resources into final application bundle under Frameworks/X.framework

5) Sign the app and nested frameworks

--
MOS_MIGRATED_REVID=100397239

1 files changed, 11 insertions, 2 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtension.java b/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtension.java
index f16327d3c2..821fa5e8e1 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtension.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtension.java
@@ -14,6 +14,8 @@
 
 package com.google.devtools.build.lib.rules.objc;
 
+import static com.google.devtools.build.lib.rules.objc.ObjcProvider.MERGE_ZIP;
+
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
@@ -48,8 +50,7 @@ public class IosExtension extends ReleaseBundlingTargetFactory {
 
   public IosExtension() {
     super(ReleaseBundlingSupport.EXTENSION_BUNDLE_DIR_FORMAT, XcodeProductType.EXTENSION,
-        ExposeAsNestedBundle.YES, ImmutableSet.of(new Attribute("binary", Mode.SPLIT)),
-        ConfigurationDistinguisher.EXTENSION);
+        ImmutableSet.of(new Attribute("binary", Mode.SPLIT)), ConfigurationDistinguisher.EXTENSION);
   }
 
   @Override
@@ -57,6 +58,14 @@ public class IosExtension extends ReleaseBundlingTargetFactory {
     return determineMinimumOsVersion(ObjcRuleClasses.objcConfiguration(ruleContext).getMinimumOs());
   }
 
+  @Override
+  protected ObjcProvider exposedObjcProvider(RuleContext ruleContext) {
+    // Nest this target's bundle under final IPA
+    return new ObjcProvider.Builder()
+        .add(MERGE_ZIP, ruleContext.getImplicitOutputArtifact(ReleaseBundlingSupport.IPA))
+        .build();
+  }
+
   private static String determineMinimumOsVersion(String fromFlag) {
     if (Double.parseDouble(fromFlag) < Double.parseDouble(EXTENSION_MINIMUM_OS_VERSION)) {
       // Extensions are not accepted by Apple below version 8.0. While applications built with a