VR: Render the keyboard through a UI renderer

This ensures that it interacts properly with other renderers. If we
render the keyboard directly, it won't flush previously-queued work, and
elements may draw out of order.

BUG=815078
R=ymalik

Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_vr;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Change-Id: Id691fea5a5a0bbbbe5f8e6d56b0ed2c33b0a8b59
Reviewed-on: https://chromium-review.googlesource.com/934981
Commit-Queue: Christopher Grant <cjgrant@chromium.org>
Reviewed-by: Yash Malik <ymalik@chromium.org>
Cr-Commit-Position: refs/heads/master@{#538890}

chrome/browser/vr/elements/keyboard.cc

@@ -113,7 +113,7 @@ void Keyboard::Render(UiElementRenderer* renderer,
   if (!delegate_)
     return;
 
-  delegate_->Draw(camera_model);
+  renderer->DrawKeyboard(camera_model, delegate_);
 }
 
 void Keyboard::OnSetFocusable() {
@@ -130,4 +130,13 @@ void Keyboard::UpdateDelegateVisibility() {
     delegate_->HideKeyboard();
 }
 
+Keyboard::Renderer::Renderer() {}
+
+Keyboard::Renderer::~Renderer() {}
+
+void Keyboard::Renderer::Draw(const CameraModel& camera_model,
+                              KeyboardDelegate* delegate) {
+  delegate->Draw(camera_model);
+}
+
 }  // namespace vr

chrome/browser/vr/elements/keyboard.h

@@ -8,6 +8,7 @@
 #include "base/macros.h"
 #include "chrome/browser/vr/elements/ui_element.h"
 #include "chrome/browser/vr/keyboard_delegate.h"
+#include "chrome/browser/vr/renderers/base_renderer.h"
 
 namespace vr {
 
@@ -31,6 +32,16 @@ class Keyboard : public UiElement {
   void OnButtonDown(const gfx::PointF& position) override;
   void OnButtonUp(const gfx::PointF& position) override;
 
+  class Renderer : public BaseRenderer {
+   public:
+    Renderer();
+    ~Renderer() override;
+    void Draw(const CameraModel& camera_model, KeyboardDelegate* delegate);
+
+   private:
+    DISALLOW_COPY_AND_ASSIGN(Renderer);
+  };
+
  private:
   bool OnBeginFrame(const base::TimeTicks& time,
                     const gfx::Transform& head_pose) override;

chrome/browser/vr/renderers/base_renderer.h

@@ -17,10 +17,11 @@ class BaseRenderer {
   virtual void Flush();
 
  protected:
+  BaseRenderer() = default;
   BaseRenderer(const char* vertex_src, const char* fragment_src);
 
-  GLuint program_handle_;
-  GLuint position_handle_;
+  GLuint program_handle_ = 0;
+  GLuint position_handle_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(BaseRenderer);
 };

chrome/browser/vr/ui_element_renderer.cc

@@ -47,6 +47,7 @@ void UiElementRenderer::Init() {
   shadow_renderer_ = std::make_unique<Shadow::Renderer>();
   stars_renderer_ = std::make_unique<Stars::Renderer>();
   background_renderer_ = std::make_unique<Background::Renderer>();
+  keyboard_renderer_ = std::make_unique<Keyboard::Renderer>();
 }
 
 void UiElementRenderer::DrawTexturedQuad(
@@ -159,6 +160,12 @@ void UiElementRenderer::DrawBackground(
                              fullscreen_factor);
 }
 
+void UiElementRenderer::DrawKeyboard(const CameraModel& camera_model,
+                                     KeyboardDelegate* delegate) {
+  FlushIfNecessary(keyboard_renderer_.get());
+  keyboard_renderer_->Draw(camera_model, delegate);
+}
+
 void UiElementRenderer::Flush() {
   textured_quad_renderer_->Flush();
   external_textured_quad_renderer_->Flush();

chrome/browser/vr/ui_element_renderer.h

@@ -13,6 +13,7 @@
 #include "chrome/browser/vr/elements/environment/background.h"
 #include "chrome/browser/vr/elements/environment/grid.h"
 #include "chrome/browser/vr/elements/environment/stars.h"
+#include "chrome/browser/vr/elements/keyboard.h"
 #include "chrome/browser/vr/elements/laser.h"
 #include "chrome/browser/vr/elements/reticle.h"
 #include "chrome/browser/vr/elements/shadow.h"
@@ -118,6 +119,9 @@ class UiElementRenderer {
       float incognito_factor,
       float fullscreen_factor);
 
+  VIRTUAL_FOR_MOCKS void DrawKeyboard(const CameraModel& camera_model,
+                                      KeyboardDelegate* delegate);
+
   void Flush();
 
  protected:
@@ -141,6 +145,7 @@ class UiElementRenderer {
   std::unique_ptr<Shadow::Renderer> shadow_renderer_;
   std::unique_ptr<Stars::Renderer> stars_renderer_;
   std::unique_ptr<Background::Renderer> background_renderer_;
+  std::unique_ptr<Keyboard::Renderer> keyboard_renderer_;
 
   DISALLOW_COPY_AND_ASSIGN(UiElementRenderer);
 };