Fix grpcio OpenSSL discovery for Android via OPENSSL_ROOT_DIR

grpcio hardcodes /usr/include/openssl for system OpenSSL. Patch
setup.py to read OPENSSL_ROOT_DIR env var and set it in the recipe
to point to the cross-compiled OpenSSL in site-packages/opt.

Author: FeodorFitsner

recipes/grpcio/meta.yaml

@@ -8,7 +8,8 @@ build:
     GRPC_PYTHON_BUILD_SYSTEM_OPENSSL: '1'
     GRPC_PYTHON_BUILD_SYSTEM_ZLIB: '1'
     PLATFORM: android
-    CFLAGS: '-U__ANDROID_API__ -D__ANDROID_API__={{ sdk_version }} -Wno-reserved-user-defined-literal -I{platlib}/opt/include'
+    OPENSSL_ROOT_DIR: '{platlib}/opt'
+    CFLAGS: '-U__ANDROID_API__ -D__ANDROID_API__={{ sdk_version }} -Wno-reserved-user-defined-literal'
     LDFLAGS: '-llog -L{platlib}/opt/lib'
 # {% else %}
     CXXFLAGS: -std=c++14 -Wno-c++11-narrowing

recipes/grpcio/patches/mobile.patch

@@ -1,5 +1,4 @@
 diff --git a/setup.py b/setup.py
-index 48bfefe..ff21bc5 100644
 --- a/setup.py
 +++ b/setup.py
 @@ -58,12 +58,14 @@ CARES_INCLUDE = (
@@ -18,22 +17,13 @@ index 48bfefe..ff21bc5 100644
  if "openbsd" in sys.platform:
      CARES_INCLUDE += (os.path.join("third_party", "cares", "config_openbsd"),)
  RE2_INCLUDE = (os.path.join("third_party", "re2"),)
-@@ -329,15 +331,16 @@ EXTENSION_INCLUDE_DIRECTORIES = (
-     + ADDRESS_SORTING_INCLUDE
-     + CARES_INCLUDE
-     + RE2_INCLUDE
--    + SSL_INCLUDE
-     + UPB_INCLUDE
-     + UPB_GRPC_GENERATED_INCLUDE
-     + UPBDEFS_GRPC_GENERATED_INCLUDE
-     + UTF8_RANGE_INCLUDE
-     + XXHASH_INCLUDE
--    + ZLIB_INCLUDE
- )
- 
-+if "android" not in sys.platform:
-+    EXTENSION_INCLUDE_DIRECTORIES += SSL_INCLUDE + ZLIB_INCLUDE
-+
- EXTENSION_LIBRARIES = ()
- if "linux" in sys.platform:
-     EXTENSION_LIBRARIES += ("rt",)
+@@ -304,7 +306,9 @@ if BUILD_WITH_SYSTEM_OPENSSL:
+     )
+     CORE_C_FILES = filter(lambda x: "src/boringssl" not in x, CORE_C_FILES)
+-    SSL_INCLUDE = (os.path.join("/usr", "include", "openssl"),)
++    # Use cross-compiled OpenSSL headers when OPENSSL_ROOT_DIR is set
++    _ssl_prefix = os.environ.get("OPENSSL_ROOT_DIR", "/usr")
++    SSL_INCLUDE = (os.path.join(_ssl_prefix, "include"),)
+
+ if BUILD_WITH_SYSTEM_ZLIB:
+     CORE_C_FILES = filter(lambda x: "third_party/zlib" not in x, CORE_C_FILES)