Remove GLImage::Destroy().

ui/gl/gl_image_memory.cc

Index: ui/gl/gl_image_memory.cc
diff --git a/ui/gl/gl_image_memory.cc b/ui/gl/gl_image_memory.cc
index 0c38c9b836d961cf10486f3d015571094a9c8e5b..8fda636947250b0f12fd7c7602f628d38bf60bf3 100644
--- a/ui/gl/gl_image_memory.cc
+++ b/ui/gl/gl_image_memory.cc
@@ -352,9 +352,7 @@ GLImageMemory::GLImageMemory(const gfx::Size& size, unsigned internalformat)
       format_(gfx::BufferFormat::RGBA_8888),
       stride_(0) {}
 
-GLImageMemory::~GLImageMemory() {
-  DCHECK(!memory_);
-}
+GLImageMemory::~GLImageMemory() {}
 
 bool GLImageMemory::Initialize(const unsigned char* memory,
                                gfx::BufferFormat format,
@@ -384,10 +382,6 @@ bool GLImageMemory::Initialize(const unsigned char* memory,
   return true;
 }
 
-void GLImageMemory::Destroy(bool have_context) {
-  memory_ = nullptr;
-}
-
 gfx::Size GLImageMemory::GetSize() {
   return size_;
 }