Add a flexible ozone configuration scheme

ui/ozone/public/ozone_platform.h

Index: ui/ozone/public/ozone_platform.h
diff --git a/ui/ozone/public/ozone_platform.h b/ui/ozone/public/ozone_platform.h
index 95e5d5bd3015c740ca7cff1c905268f30a2317a7..5757660809d25f9864b46a9fef17a7188e54bed1 100644
--- a/ui/ozone/public/ozone_platform.h
+++ b/ui/ozone/public/ozone_platform.h
@@ -14,6 +14,11 @@ namespace gfx {
 class Rect;
 }
 
+namespace shell {
+class Connector;
+class Connection;
+}
+
 namespace ui {
 
 class CursorFactoryOzone;
@@ -46,13 +51,39 @@ class OZONE_EXPORT OzonePlatform {
   OzonePlatform();
   virtual ~OzonePlatform();
 
+  // Additional initalization params for the platform. Platforms must not retain
+  // a reference to this structure.
+  struct InitParams {
+    // Ozone may retain this pointer for later use. An Ozone platform embedder
+    // must set this parameter in order for the Ozone platform implementation to
+    // be able to use Mojo.
+    shell::Connector* connector = nullptr;
+
+    // Setting this to true indicates that the platform implementation should
+    // operate as a single process for platforms (i.e. drm) that are usually
+    // split between a main and gpu specific portion.
+    bool single_process = false;
+  };
+
   // Initializes the subsystems/resources necessary for the UI process (e.g.
-  // events, surface, etc.)
+  // events, etc.)
+  // TODO(rjkroege): Remove deprecated entry point (http://crbug.com/620934)
   static void InitializeForUI();
 
-  // Initializes the subsystems/resources necessary for the GPU process.
+  // Initializes the subsystems/resources necessary for the UI process (e.g.
+  // events) with additional properties to customize the ozone platform
+  // implementation. Ozone will not retain InitParams after returning from
+  // InitalizeForUI.
+  static void InitializeForUI(const InitParams& args);
+
+  // Initializes the subsystems/resources necessary for rendering (i.e. GPU).
+  // TODO(rjkroege): Remove deprecated entry point (http://crbug.com/620934)
   static void InitializeForGPU();
 
+  // Initializes the subsystems for rendering but with additional properties
+  // provided by |args| as with InitalizeForUI.
+  static void InitializeForGPU(const InitParams& args);
+
   static OzonePlatform* GetInstance();
 
   // Factory getters to override in subclasses. The returned objects will be
@@ -71,9 +102,20 @@ class OZONE_EXPORT OzonePlatform {
   virtual std::unique_ptr<ui::NativeDisplayDelegate>
   CreateNativeDisplayDelegate() = 0;
 
+  // Ozone platform implementations may also choose to expose mojo interfaces to
+  // internal functionality. Embedders wishing to take advantage of ozone mojo
+  // implementations must invoke AddInterfaces with a valid shell::Connection*
+  // pointer to export all Mojo interfaces defined within Ozone.
+  //
+  // A default do-nothing implementation is provided to permit platform
+  // implementations to opt out of implementing any Mojo interfaces.
+  virtual void AddInterfaces(shell::Connection* connection);
+
  private:
   virtual void InitializeUI() = 0;
   virtual void InitializeGPU() = 0;
+  virtual void InitializeUI(const InitParams& args);
+  virtual void InitializeGPU(const InitParams& args);
 
   static void CreateInstance();