Add StructuredData plugin type; showcase with new DarwinLog feature

Take 2, with missing cmake line fixed.  Build tested on
Ubuntu 14.04 with clang-3.6.

See docs/structured_data/StructuredDataPlugins.md for details.

differential review: https://reviews.llvm.org/D22976

reviewers: clayborg, jingham
llvm-svn: 279202
diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
index 0f41a21..3a0dd2f 100644
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
@@ -261,6 +261,10 @@
     StructuredData::ObjectSP
     GetLoadedDynamicLibrariesInfos (lldb::addr_t image_list_address, lldb::addr_t image_count) override;
 
+    Error
+    ConfigureStructuredData(const ConstString &type_name,
+                            const StructuredData::ObjectSP &config_sp) override;
+
     StructuredData::ObjectSP
     GetLoadedDynamicLibrariesInfos () override;
 
@@ -506,6 +510,9 @@
     HandleAsyncMisc(llvm::StringRef data) override;
     void
     HandleStopReply() override;
+    bool
+    HandleAsyncStructuredData(const StructuredData::ObjectSP
+                              &object_sp) override;
 
     DISALLOW_COPY_AND_ASSIGN (ProcessGDBRemote);
 };