GPU: Add draw for immediate and batch modes

PR #1461 introduced a regression where some games would change configuration
even while in the poorly named "drawing" mode, which broke the heuristic
citra was using to determine when to draw the batch. This change adds
back in a draw call for batching, and also adds in a draw call in
immediate mode each time it adds a triangle.

src/video_core/command_processor.cpp

@@ -243,6 +243,15 @@ static void WritePicaReg(u32 id, u32 value, u32 mask) {
                     ASSERT(!g_state.geometry_pipeline.NeedIndexInput());
                     g_state.geometry_pipeline.Setup(shader_engine);
                     g_state.geometry_pipeline.SubmitVertex(output);
+
+                    // TODO: If drawing after every immediate mode triangle kills performance,
+                    // change it to flush triangles whenever a draing config register changes
+                    // See: https://github.com/citra-emu/citra/pull/2866#issuecomment-327011550
+                    VideoCore::g_renderer->Rasterizer()->DrawTriangles();
+                    if (g_debug_context) {
+                        g_debug_context->OnEvent(DebugContext::Event::FinishedPrimitiveBatch,
+                                                 nullptr);
+                    }
                 }
             }
         }
@@ -398,6 +407,12 @@ static void WritePicaReg(u32 id, u32 value, u32 mask) {
                                                       range.second, range.first);
         }
 
+        MICROPROFILE_SCOPE(GPU_Drawing);
+        VideoCore::g_renderer->Rasterizer()->DrawTriangles();
+        if (g_debug_context) {
+            g_debug_context->OnEvent(DebugContext::Event::FinishedPrimitiveBatch, nullptr);
+        }
+
         break;
     }
 
@@ -632,6 +647,6 @@ void ProcessCommandList(const u32* list, u32 size) {
     }
 }
 
-} // namespace
+} // namespace CommandProcessor
 
-} // namespace
+} // namespace Pica