Remove CPDFSDK_Annot::ResetAppearance().

It's unused, and it caused a warning about CPDFSDK_Widget::ResetAppearance()
failing to override it (since these two unrelated methods had the same name).

No intended behavior change.

BUG=pdfium:29
R=bo_xu@foxitsoftware.com

Review URL: https://codereview.chromium.org/429483004

fpdfsdk/include/fsdk_baseannot.h

diff --git a/fpdfsdk/include/fsdk_baseannot.h b/fpdfsdk/include/fsdk_baseannot.h
index 4642508..50a6e1e 100644
--- a/fpdfsdk/include/fsdk_baseannot.h
+++ b/fpdfsdk/include/fsdk_baseannot.h
@@ -160,7 +160,6 @@
 	
 	void						ClearCachedAP();
 	
-	virtual void				ResetAppearance();
 	void						WriteAppearance(const CFX_ByteString& sAPType, const CPDF_Rect& rcBBox, 
 		const CPDF_Matrix& matrix, const CFX_ByteString& sContents,
 		const CFX_ByteString& sAPState = "");

fpdfsdk/src/fsdk_baseannot.cpp

diff --git a/fpdfsdk/src/fsdk_baseannot.cpp b/fpdfsdk/src/fsdk_baseannot.cpp
index c8e0735..ff054c8 100644
--- a/fpdfsdk/src/fsdk_baseannot.cpp
+++ b/fpdfsdk/src/fsdk_baseannot.cpp
@@ -596,11 +596,6 @@
 	return "";
 }
 
-void CPDFSDK_Annot::ResetAppearance()
-{
-	ASSERT(FALSE);
-}
-
 void CPDFSDK_Annot::DrawAppearance(CFX_RenderDevice* pDevice, const CPDF_Matrix* pUser2Device,
 								   CPDF_Annot::AppearanceMode mode, const CPDF_RenderOptions* pOptions)	
 {