Make Framebuffer::checkStatus non-const.

BUG=angleproject:1388

Change-Id: Ia9befba0c915c087f2fe0557d91060256f6d4950
Reviewed-on: https://chromium-review.googlesource.com/348955
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
diff --git a/src/libANGLE/Framebuffer.cpp b/src/libANGLE/Framebuffer.cpp
index cb1f97d..6d5c998 100644
--- a/src/libANGLE/Framebuffer.cpp
+++ b/src/libANGLE/Framebuffer.cpp
@@ -388,7 +388,7 @@
     return false;
 }
 
-GLenum Framebuffer::checkStatus(const ContextState &state) const
+GLenum Framebuffer::checkStatus(const ContextState &state)
 {
     // The default framebuffer *must* always be complete, though it may not be
     // subject to the same rules as application FBOs. ie, it could have 0x0 size.
@@ -743,7 +743,7 @@
     return mImpl->blit(context, sourceArea, destArea, mask, filter);
 }
 
-int Framebuffer::getSamples(const ContextState &state) const
+int Framebuffer::getSamples(const ContextState &state)
 {
     if (checkStatus(state) == GL_FRAMEBUFFER_COMPLETE)
     {
@@ -836,4 +836,18 @@
     }
 }
 
+int Framebuffer::getCachedSamples(const ContextState &state) const
+{
+    // TODO(jmadill): Framebuffer samples caching.
+    ASSERT(mDirtyBits.none());
+    return const_cast<Framebuffer *>(this)->getSamples(state);
+}
+
+GLenum Framebuffer::getCachedStatus(const ContextState &state) const
+{
+    // TODO(jmadill): Framebuffer status caching.
+    ASSERT(mDirtyBits.none());
+    return const_cast<Framebuffer *>(this)->checkStatus(state);
+}
+
 }  // namespace gl