Work around BoringSSL bitcode linker warning (#470)

* Work around BoringSSL bitcode linker warning

When linking envoy-mobile to an iOS app that ships with bitcode, you get
these warnings from the linker:

```
ld: warning: Linker asked to preserve internal global: 'sk_CRYPTO_BUFFER_call_free_func'
ld: warning: Linker asked to preserve internal global: 'sk_X509_call_free_func'
ld: warning: Linker asked to preserve internal global: 'sk_X509_call_free_func'
ld: warning: Linker asked to preserve internal global: 'sk_X509_call_free_func'
ld: warning: Linker asked to preserve internal global: 'sk_X509_call_free_func'
```

I have submitted an upstream patch to fix this
https://boringssl-review.googlesource.com/c/boringssl/+/37804 in the
meantime I've applied that patch here.

Signed-off-by: Keith Smiley <[email protected]>
Signed-off-by: JP Simard <[email protected]>

mobile/WORKSPACE

@@ -13,6 +13,16 @@ http_archive(
     urls = ["https://github.com/abseil/abseil-cpp/archive/61c9bf3e3e1c28a4aa6d7f1be4b37fd473bb5529.tar.gz"],
 )
 
+# This should be kept in sync with Envoy itself, we just need to apply this patch
+# Remove this once https://boringssl-review.googlesource.com/c/boringssl/+/37804 is in master-with-bazel
+http_archive(
+    name = "boringssl",
+    patches = ["//bazel:boringssl.patch"],
+    sha256 = "36049e6cd09b353c83878cae0dd84e8b603ba1a40dcd74e44ebad101fc5c672d",
+    strip_prefix = "boringssl-37b57ed537987f1b4c60c60fa1aba20f3a0f6d26",
+    urls = ["https://github.com/google/boringssl/archive/37b57ed537987f1b4c60c60fa1aba20f3a0f6d26.tar.gz"],
+)
+
 local_repository(
     name = "envoy",
     path = "envoy",

mobile/bazel/boringssl.patch

@@ -0,0 +1,11 @@
+--- src/include/openssl/base.h
++++ src/include/openssl/base.h
+@@ -258,7 +258,7 @@ extern "C" {
+ // with the old gnu89 model:
+ // https://stackoverflow.com/questions/216510/extern-inline
+ #if defined(__cplusplus)
+-#define OPENSSL_INLINE inline
++#define OPENSSL_INLINE static inline
+ #else
+ // Add OPENSSL_UNUSED so that, should an inline function be emitted via macro
+ // (e.g. a |STACK_OF(T)| implementation) in a source file without tripping