Reland of Mojo: Eliminate duplicate C API symbols

mojo/edk/embedder/BUILD.gn

Index: mojo/edk/embedder/BUILD.gn
diff --git a/mojo/edk/embedder/BUILD.gn b/mojo/edk/embedder/BUILD.gn
index e822b196ceb92fc30796602329c7e8fa1412a474..529aea3b4913b4db2b140a36abdcd0707185c844 100644
--- a/mojo/edk/embedder/BUILD.gn
+++ b/mojo/edk/embedder/BUILD.gn
@@ -37,6 +37,7 @@
     "embedder.h",
     "embedder_internal.h",
     "entrypoints.cc",
+    "entrypoints.h",
 
     # Test-only code:
     # TODO(vtl): It's a little unfortunate that these end up in the same
@@ -46,12 +47,7 @@
     "test_embedder.h",
   ]
 
-  defines = [
-    "MOJO_SYSTEM_IMPL_IMPLEMENTATION",
-    "MOJO_SYSTEM_IMPLEMENTATION",
-  ]
-
-  configs += [ "//mojo/edk/system:system_config" ]
+  defines = [ "MOJO_SYSTEM_IMPL_IMPLEMENTATION" ]
 
   public_deps = [
     ":delegates",
@@ -98,8 +94,6 @@
 
   defines = [ "MOJO_SYSTEM_IMPL_IMPLEMENTATION" ]
 
-  configs += [ "//mojo/edk/system:system_config" ]
-
   public_deps = [
     "//mojo/public/cpp/system",
   ]
@@ -131,8 +125,6 @@
 
   defines = [ "MOJO_SYSTEM_IMPL_IMPLEMENTATION" ]
 
-  configs += [ "//mojo/edk/system:system_config" ]
-
   public_deps = [
     "//mojo/public/cpp/system",
   ]