Fix snapshotting on linux by creating a separate automation path for

chrome/common/automation_messages_internal.h

Index: chrome/common/automation_messages_internal.h
diff --git a/chrome/common/automation_messages_internal.h b/chrome/common/automation_messages_internal.h
index ac032dbb9eefd7a19458dfe4a0d6894140351eef..85dec1b6c44ed5aadda5409aa50c1afaee32a2dd 100644
--- a/chrome/common/automation_messages_internal.h
+++ b/chrome/common/automation_messages_internal.h
@@ -1476,8 +1476,19 @@ IPC_SYNC_MESSAGE_CONTROL1_2(AutomationMsg_IsBrowserInApplicationMode,
                             bool /* is_application */,
                             bool /* success */)
 
+// Browser -> renderer messages.
+
+// Requests a snapshot.
+IPC_MESSAGE_ROUTED0(AutomationMsg_SnapshotEntirePage)
+
 // Renderer -> browser messages.
 
+// Sent as a response to |AutomationMsg_Snapshot|.
+IPC_MESSAGE_ROUTED3(AutomationMsg_SnapshotEntirePageACK,
+                    bool /* success */,
+                    std::vector<unsigned char> /* png bytes */,
+                    std::string /* error message */)
+
 // Sent when the renderer has scheduled a client redirect to occur.
 IPC_MESSAGE_ROUTED2(AutomationMsg_WillPerformClientRedirect,
                     int64 /* frame_id */,