Add support for SBProcess::PutSTDIN to remote processes

Processes running on a remote target can already send $O messages
to send stdout but there is no way to send stdin to a remote
inferior.

This allows processes using the API to pump stdin into a remote
inferior process.

It fixes a hang in TestProcessIO.py when running against a remote
target.

llvm-svn: 228419
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
index 0338c26..d90614b 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
@@ -175,6 +175,23 @@
 
 
     //------------------------------------------------------------------
+    /// Sends a GDB remote protocol 'I' packet that delivers stdin
+    /// data to the remote process.
+    ///
+    /// @param[in] data
+    ///     A pointer to stdin data.
+    ///
+    /// @param[in] data_len
+    ///     The number of bytes available at \a data.
+    ///
+    /// @return
+    ///     Zero if the attach was successful, or an error indicating
+    ///     an error code.
+    //------------------------------------------------------------------
+    int
+    SendStdinNotification(const char* data, size_t data_len);
+
+    //------------------------------------------------------------------
     /// Sets the path to use for stdin/out/err for a process
     /// that will be launched with the 'A' packet.
     ///