Reland: Update FlatBuffers to include multiple improvements.

third_party/flatbuffers/BUILD.gn

Index: third_party/flatbuffers/BUILD.gn
diff --git a/third_party/flatbuffers/BUILD.gn b/third_party/flatbuffers/BUILD.gn
index b48a36659269634d110e83f19926d76df2efd848..6407c35d7cd35e61ae87abba784c85a2a4a82bbf 100644
--- a/third_party/flatbuffers/BUILD.gn
+++ b/third_party/flatbuffers/BUILD.gn
@@ -9,26 +9,45 @@ config("flatbuffers_config") {
   include_dirs = [ "src/include" ]
 }
 
+# The part of FlatBuffers that Chrome is interested in.
 source_set("flatbuffers") {
   sources = [
     "src/include/flatbuffers/flatbuffers.h",
-    "src/include/flatbuffers/hash.h",
   ]
 
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [ "//build/config/compiler:no_chromium_code" ]
+
   public_configs = [ ":flatbuffers_config" ]
 }
 
+# The complete FlatBuffers library, as required to build the flatc compiler and
+# some of the tests.
 source_set("compiler_files") {
+  include_dirs = [ "src/grpc" ]
   sources = [
+    "src/grpc/src/compiler/config.h",
+    "src/grpc/src/compiler/cpp_generator.cc",
+    "src/grpc/src/compiler/cpp_generator.h",
+    "src/grpc/src/compiler/go_generator.cc",
+    "src/grpc/src/compiler/go_generator.h",
+    "src/grpc/src/compiler/schema_interface.h",
     "src/include/flatbuffers/code_generators.h",
+    "src/include/flatbuffers/flatc.h",
+    "src/include/flatbuffers/flexbuffers.h",
+    "src/include/flatbuffers/grpc.h",
+    "src/include/flatbuffers/hash.h",
     "src/include/flatbuffers/idl.h",
+    "src/include/flatbuffers/reflection.h",
+    "src/include/flatbuffers/reflection_generated.h",
     "src/include/flatbuffers/util.h",
+    "src/src/code_generators.cpp",
+    "src/src/flatc.cpp",
     "src/src/idl_gen_cpp.cpp",
     "src/src/idl_gen_fbs.cpp",
     "src/src/idl_gen_general.cpp",
     "src/src/idl_gen_go.cpp",
+    "src/src/idl_gen_grpc.cpp",
     "src/src/idl_gen_js.cpp",
     "src/src/idl_gen_php.cpp",
     "src/src/idl_gen_python.cpp",
@@ -45,7 +64,7 @@ source_set("compiler_files") {
 
 executable("flatc") {
   sources = [
-    "src/src/flatc.cpp",
+    "src/src/flatc_main.cpp",
   ]
   deps = [
     ":compiler_files",
@@ -60,25 +79,18 @@ flatbuffer("flatbuffers_samplebuffer") {
   testonly = true
   sources = [
     # Disabled as workaround for crbug.com/611351
-    # "src/tests/include_test1.fbs",
-    # "src/tests/include_test2.fbs",
+    # "src/tests/include_test/include_test1.fbs",
+    # "src/tests/include_test/sub/include_test2.fbs",
     "src/tests/monster_test.fbs",
     "src/tests/namespace_test/namespace_test1.fbs",
     "src/tests/namespace_test/namespace_test2.fbs",
   ]
+  flatc_include_dirs = [ "src/tests/include_test" ]
 }
 
 test("flatbuffers_unittest") {
   sources = [
-    # The following files are not included in :flatbuffers
-    # but are listed here because test.cpp tests more than what will
-    # get included into Chrome (reflection and generation).
-    "src/include/reflection.h",
-    "src/include/reflection_generated.h",
-
-    # This is the actual test.
     "src/tests/test.cpp",
-    "src/tests/test.h",
   ]
   deps = [
     ":compiler_files",
@@ -88,4 +100,10 @@ test("flatbuffers_unittest") {
   data = [
     "src/tests/",
   ]
+
+  if (is_win) {
+    # Suppress "object allocated on the heap may not be aligned 16".
+    cflags = [ "/wd4316" ]
+  }
+  defines = [ "FLATBUFFERS_TRACK_VERIFIER_BUFFER_SIZE" ]
 }