EDK: Remove MOJO_SYSTEM_IMPL_EXPORT, system_impl_export.h, etc.

mojo/edk/system/master_connection_manager.cc

Index: mojo/edk/system/master_connection_manager.cc
diff --git a/mojo/edk/system/master_connection_manager.cc b/mojo/edk/system/master_connection_manager.cc
index 31521e8a135735f3a8617e3e1c186ae9a46d139b..dd8da3a0abdd026c83ec71ae8a387c7b0fcee616 100644
--- a/mojo/edk/system/master_connection_manager.cc
+++ b/mojo/edk/system/master_connection_manager.cc
@@ -66,8 +66,7 @@ MessageInTransit::Subtype ConnectionManagerResultToMessageInTransitSubtype(
 
 // |MasterConnectionManager::Helper| is not thread-safe, and must only be used
 // on its |owner_|'s private thread.
-class MOJO_SYSTEM_IMPL_EXPORT MasterConnectionManager::Helper final
-    : public RawChannel::Delegate {
+class MasterConnectionManager::Helper final : public RawChannel::Delegate {
  public:
   Helper(MasterConnectionManager* owner,
          ProcessIdentifier process_identifier,
@@ -226,7 +225,7 @@ void MasterConnectionManager::Helper::FatalError() {
 
 // MasterConnectionManager::PendingConnectInfo ---------------------------------
 
-struct MOJO_SYSTEM_IMPL_EXPORT MasterConnectionManager::PendingConnectInfo {
+struct MasterConnectionManager::PendingConnectInfo {
   // States:
   //   - This is created upon a first "allow connect" (with |first| set
   //     immediately). We then wait for a second "allow connect".