[third_party/protobuf] Modify how depreacated fields are allowed.

recently protobuf added a deprecated annotation to C++ code to warn when
depreacated protobuf fields are in use. To allow continue use of
deprecated fields in C++, a compiler exception was added. This turned
out to be pretty widespread. Will disable for now protobuf deprecated
warnings and remove the extra GN config so that the exception doesn't
need to be present.

Bug: 1151621
Change-Id: I9216c94079f90231f2cea81d9f46b6a39b0037fe
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2553387
Commit-Queue: Andres Medina <medinaandres@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Auto-Submit: Andres Medina <medinaandres@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830021}

third_party/protobuf/BUILD.gn

@@ -25,9 +25,7 @@ config("protobuf_warnings") {
   cflags = []
   if (is_clang) {
     # protobuf-3 contains a few functions that are unused.
-    cflags += [
-      "-Wno-unused-function" ,
-    ]
+    cflags += [ "-Wno-unused-function" ]
   }
 }
 
@@ -35,9 +33,7 @@ config("protoc_warnings") {
   cflags = []
   if (is_clang) {
     # Some generates contain a few fields that are not used.
-    cflags += [
-      "-Wno-unused-private-field" ,
-    ]
+    cflags += [ "-Wno-unused-private-field" ]
   }
 }
 
@@ -58,7 +54,7 @@ config("using_proto") {
 
 config("allow_deprecated_proto_fields") {
   if (is_clang) {
-    cflags = [  "-Wno-deprecated-declarations" ]
+    cflags = [ "-DPROTOBUF_ALLOW_DEPRECATED=1" ]
   }
 }
 
@@ -93,8 +89,8 @@ protobuf_lite_sources = [
   "src/google/protobuf/io/zero_copy_stream_impl.h",
   "src/google/protobuf/io/zero_copy_stream_impl_lite.cc",
   "src/google/protobuf/io/zero_copy_stream_impl_lite.h",
-  "src/google/protobuf/map.h",
   "src/google/protobuf/map.cc",
+  "src/google/protobuf/map.h",
   "src/google/protobuf/map_entry_lite.h",
   "src/google/protobuf/map_field_lite.h",
   "src/google/protobuf/map_type_handler.h",

third_party/protobuf/README.chromium

@@ -75,3 +75,8 @@ Description of the patches:
 - 0021-Fix-protobuf-s-library-.gitinore-file.patch
 
   Un-ignores python/google/protobuf/descriptor_pb2.py
+
+
+- 0022-Allow-deprecated-fields.patch
+
+  Allows depreacated fields to be used without extra C++ compiler warnings.
\ No newline at end of file

third_party/protobuf/patches/0022-Allow-deprecated-fields.patch

+diff --git a/src/google/protobuf/port_def.inc b/src/google/protobuf/port_def.inc
+index 19e71f80c..4283ed099 100644
+--- a/src/google/protobuf/port_def.inc
++++ b/src/google/protobuf/port_def.inc
+@@ -150,6 +150,11 @@
+   } /* namespace protobuf */     \
+   } /* namespace google */
+ 
++#ifdef PROTOBUF_ALLOW_DEPRECATED
++#define PROTOBUF_DEPRECATED
++#define PROTOBUF_DEPRECATED_ENUM
++#define PROTOBUF_DEPRECATED_MSG(msg)
++#else
+ #if defined(__GNUC__) || defined(__clang__)
+ #define PROTOBUF_DEPRECATED __attribute__((deprecated))
+ #define PROTOBUF_DEPRECATED_ENUM __attribute__((deprecated))
+@@ -159,6 +164,7 @@
+ #define PROTOBUF_DEPRECATED_ENUM
+ #define PROTOBUF_DEPRECATED_MSG(msg) __declspec(deprecated(msg))
+ #endif
++#endif
+ 
+ #define PROTOBUF_SECTION_VARIABLE(x)
+ #define PROTOBUF_MUST_USE_RESULT

third_party/protobuf/src/google/protobuf/port_def.inc

@@ -150,6 +150,11 @@
   } /* namespace protobuf */     \
   } /* namespace google */
 
+#ifdef PROTOBUF_ALLOW_DEPRECATED
+#define PROTOBUF_DEPRECATED
+#define PROTOBUF_DEPRECATED_ENUM
+#define PROTOBUF_DEPRECATED_MSG(msg)
+#else
 #if defined(__GNUC__) || defined(__clang__)
 #define PROTOBUF_DEPRECATED __attribute__((deprecated))
 #define PROTOBUF_DEPRECATED_ENUM __attribute__((deprecated))
@@ -159,6 +164,7 @@
 #define PROTOBUF_DEPRECATED_ENUM
 #define PROTOBUF_DEPRECATED_MSG(msg) __declspec(deprecated(msg))
 #endif
+#endif
 
 #define PROTOBUF_SECTION_VARIABLE(x)
 #define PROTOBUF_MUST_USE_RESULT