[BitmapTexture] Check EGL context before destruction

Destroying GL resources without EGL context bound is not safe
and may lead to crash.

Author: asurdej-comcast

Source/WebCore/platform/graphics/texmap/BitmapTexture.cpp

@@ -288,6 +288,12 @@ void BitmapTexture::bindAsSurface()
 
 BitmapTexture::~BitmapTexture()
 {
+    GLContext* currentContext = GLContext::current();
+    if (!currentContext || !currentContext->platformContext()) {
+        // The context has been destroyed already, so we can't clean up.
+        return;
+    }
+
     glDeleteTextures(1, &m_id);
 
     if (m_fbo)