EDK: Add implementation of data pipe producer write threshold stuff.

mojo/public/platform/native/system_impl_private_unittest.cc

Index: mojo/public/platform/native/system_impl_private_unittest.cc
diff --git a/mojo/public/platform/native/system_impl_private_unittest.cc b/mojo/public/platform/native/system_impl_private_unittest.cc
index 900c93271ff5c887d8cabe699532d2c7a3da625a..f54b5e36f40a7034380b2b7814933f7f89dfeb70 100644
--- a/mojo/public/platform/native/system_impl_private_unittest.cc
+++ b/mojo/public/platform/native/system_impl_private_unittest.cc
@@ -168,8 +168,10 @@ TEST(SystemImplTest, BasicDataPipe) {
       MOJO_RESULT_OK,
       MojoSystemImplWait(sys0, hp, MOJO_HANDLE_SIGNAL_WRITABLE, 0, &state));
 
-  EXPECT_EQ(MOJO_HANDLE_SIGNAL_WRITABLE, state.satisfied_signals);
-  EXPECT_EQ(MOJO_HANDLE_SIGNAL_WRITABLE | MOJO_HANDLE_SIGNAL_PEER_CLOSED,
+  EXPECT_EQ(MOJO_HANDLE_SIGNAL_WRITABLE | MOJO_HANDLE_SIGNAL_WRITE_THRESHOLD,
+            state.satisfied_signals);
+  EXPECT_EQ(MOJO_HANDLE_SIGNAL_WRITABLE | MOJO_HANDLE_SIGNAL_PEER_CLOSED |
+                MOJO_HANDLE_SIGNAL_WRITE_THRESHOLD,
             state.satisfiable_signals);
 
   // Try to read from |hc|.
@@ -267,6 +269,9 @@ TEST(SystemImplTest, BasicDataPipe) {
   // 2 SystemImpls are leaked...
 }
 
+// TODO(vtl): Once thunks are in:
+//   TEST(SystemImplTest, DataPipeWriteThreshold) { ... }
+
 TEST(SystemImplTest, DataPipeReadThreshold) {
   MojoSystemImpl sys0 = MojoSystemImplCreateImpl();
   MojoSystemImpl sys1 = MojoSystemImplCreateImpl();