Bug 1428182 - 5. Update libevent patch for Android builds; r=froydnj

Support for accept4 and arc4random_buf depends on which set of NDK
headers we're using. accept4 is supported for API >= 21 for unified and
non-unified headers. arc4random_buf is supported for API >= 21 if using
non-unified headers, and it's always supported if using unified headers
(the unified headers provide shims for API < 21).

MozReview-Commit-ID: FY8n5jWXB1K

--HG--
rename : ipc/chromium/src/third_party/libevent/patches/android-arc4random-buf.patch => ipc/chromium/src/third_party/libevent/patches/android-api-level.patch
extra : rebase_source : a8974cb1e8e71a8c951754ca9902fff28c099031

ipc/chromium/src/third_party/libevent/README.mozilla

@@ -34,5 +34,5 @@ ipc/chromium/src/third_party/libevent/patches/:
 - "linux-no-sysctl.patch". Fixes the build on Linux systems without sysctl.h.
   See bug 1263429.
 
-- "android-arc4random-buf.patch". Fixes the build for clang/android builds.
-  See bug 1281596 and bug 1282141.
+- "android-api-level.patch". Fixes the build under clang or NDK r16.
+  See bug 1281596, bug 1282141, and bug 1428182.

ipc/chromium/src/third_party/libevent/android/event2/event-config.h

@@ -24,13 +24,21 @@
 /* #undef EVENT__DISABLE_THREAD_SUPPORT */
 
 /* Define to 1 if you have the `accept4' function. */
+#if __ANDROID_API__ >= 21
 #define EVENT__HAVE_ACCEPT4 1
+#else
+/* #undef EVENT__HAVE_ACCEPT4 */
+#endif
 
 /* Define to 1 if you have the `arc4random' function. */
 #define EVENT__HAVE_ARC4RANDOM 1
 
 /* Define to 1 if you have the `arc4random_buf' function. */
+#if __ANDROID_API__ >= 21 || defined(__ANDROID_API_L__)
+#define EVENT__HAVE_ARC4RANDOM_BUF 1
+#else
 /* #undef EVENT__HAVE_ARC4RANDOM_BUF */
+#endif
 
 /* Define to 1 if you have the <arpa/inet.h> header file. */
 #define EVENT__HAVE_ARPA_INET_H 1

ipc/chromium/src/third_party/libevent/patches/android-api-level.patch

@@ -1,17 +1,30 @@
 diff --git a/ipc/chromium/src/third_party/libevent/android/event2/event-config.h b/ipc/chromium/src/third_party/libevent/android/event2/event-config.h
 --- a/ipc/chromium/src/third_party/libevent/android/event2/event-config.h
 +++ b/ipc/chromium/src/third_party/libevent/android/event2/event-config.h
-@@ -25,17 +25,17 @@
+@@ -19,23 +19,31 @@
+ 
+ /* Define if libevent should not allow replacing the mm functions */
+ /* #undef EVENT__DISABLE_MM_REPLACEMENT */
+ 
+ /* Define if libevent should not be compiled with thread support */
+ /* #undef EVENT__DISABLE_THREAD_SUPPORT */
  
  /* Define to 1 if you have the `accept4' function. */
++#if __ANDROID_API__ >= 21
  #define EVENT__HAVE_ACCEPT4 1
++#else
++/* #undef EVENT__HAVE_ACCEPT4 */
++#endif
  
  /* Define to 1 if you have the `arc4random' function. */
  #define EVENT__HAVE_ARC4RANDOM 1
  
  /* Define to 1 if you have the `arc4random_buf' function. */
--#define EVENT__HAVE_ARC4RANDOM_BUF 1
++#if __ANDROID_API__ >= 21 || defined(__ANDROID_API_L__)
+ #define EVENT__HAVE_ARC4RANDOM_BUF 1
++#else
 +/* #undef EVENT__HAVE_ARC4RANDOM_BUF */
++#endif
  
  /* Define to 1 if you have the <arpa/inet.h> header file. */
  #define EVENT__HAVE_ARPA_INET_H 1