[clang] Adding support for NSMakeCollectable and CFMakeCollectable

Summary:
@public
Adding support for NSMakeCollectable and CFMakeCollectable.
Fixes issue https://github.com/facebook/infer/issues/116

Test Plan:
Tested on the example of the issue https://github.com/facebook/infer/issues/116
and we don't get the leak there anymore.

infer/models/objc/src/CoreFoundation/CFType.c

@@ -0,0 +1,5 @@
+#import <Foundation/Foundation.h>
+
+CFTypeRef CFMakeCollectable ( CFTypeRef cf ) {
+    return cf;
+}

infer/src/clang/cFrontend_config.ml

@@ -106,6 +106,8 @@ let cf_bridging_retain = "CFBridgingRetain"
 
 let cf_autorelease = "CFAutorelease"
 
+let ns_make_collectable = "NSMakeCollectable"
+
 let builtin_expect = "__builtin_expect"
 
 let builtin_memset_chk = "__builtin___memset_chk"

infer/src/clang/cFrontend_config.mli

@@ -103,6 +103,8 @@ val cf_bridging_retain : string
 
 val cf_autorelease : string
 
+val ns_make_collectable : string
+
 val builtin_expect : string
 
 val builtin_memset_chk : string

infer/src/clang/cTrans_models.ml

@@ -90,7 +90,8 @@ let is_toll_free_bridging pn_opt =
       let funct = (Procname.to_string pn) in
       funct = CFrontend_config.cf_bridging_release ||
       funct = CFrontend_config.cf_bridging_retain ||
-      funct = CFrontend_config.cf_autorelease
+      funct = CFrontend_config.cf_autorelease ||
+      funct = CFrontend_config.ns_make_collectable
   | None -> false
 
 (** If the function is a builtin model, return the model, otherwise return the function *)

infer/tests/codetoanalyze/objc/errors/memory_leaks_benchmark/NSMakeCollectableExample.m

@@ -0,0 +1,19 @@
+#import <Foundation/Foundation.h>
+
+@interface E : NSObject
+
+@end
+
+@implementation E
+
+- (CFReadStreamRef) readStream {
+    return nil;
+}
+
+- (void) handleStreamError
+{
+    NSError *underlyingError = NSMakeCollectable(
+        [(NSError*)CFReadStreamCopyError((CFReadStreamRef)[self readStream]) autorelease]);
+}
+
+@end

infer/tests/endtoend/objc/NSMakeCollectableTest.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2013- Facebook.
+ * All rights reserved.
+ */
+
+package endtoend.objc;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static utils.matchers.ResultContainsExactly.containsExactly;
+
+import com.google.common.collect.ImmutableList;
+
+import org.junit.BeforeClass;
+import org.junit.ClassRule;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import utils.DebuggableTemporaryFolder;
+import utils.InferException;
+import utils.InferResults;
+import utils.InferRunner;
+
+public class NSMakeCollectableTest {
+
+  public static final String memory_leak_file =
+      "infer/tests/codetoanalyze/objc/errors/memory_leaks_benchmark/NSMakeCollectableExample.m";
+
+  private static ImmutableList<String> inferCmd;
+
+  public static final String MEMORY_LEAK = "MEMORY_LEAK";
+
+  @ClassRule
+  public static DebuggableTemporaryFolder folder =
+      new DebuggableTemporaryFolder();
+
+  @BeforeClass
+  public static void runInfer() throws InterruptedException, IOException {
+    inferCmd = InferRunner.createObjCInferCommandWithMLBuckets(
+        folder,
+        memory_leak_file,
+        "cf",
+        false);
+  }
+
+  @Test
+  public void whenInferRunsOnTestWithBucketingThenMLIsNotFound()
+      throws InterruptedException, IOException, InferException {
+    InferResults inferResults = InferRunner.runInferObjC(inferCmd);
+    String[] procedures = {
+    };
+    assertThat(
+        "Results should not contain memory leak",
+        inferResults,
+        containsExactly(
+            MEMORY_LEAK,
+            memory_leak_file,
+            procedures));
+  }
+
+
+}