Cleanup: Remove deprecated method.

public/platform/WebCrypto.h

Index: public/platform/WebCrypto.h
diff --git a/public/platform/WebCrypto.h b/public/platform/WebCrypto.h
index 95197b63240f02003b3cea87361bf6acfba540cf..2d8dc5f957e4a712229509b6d664accac0da7e08 100644
--- a/public/platform/WebCrypto.h
+++ b/public/platform/WebCrypto.h
@@ -44,7 +44,6 @@ namespace WTF { template <typename T> class PassRefPtr; }
 namespace WebKit {
 
 class WebArrayBuffer;
-class WebCryptoOperation;
 
 class WebCryptoResult {
 public:
@@ -84,9 +83,6 @@ private:
 
 class WebCrypto {
 public:
-    // FIXME: Deprecated, delete once chromium side is updated.
-    virtual WebCryptoOperation* digest(const WebCryptoAlgorithm&) { WEBKIT_ASSERT_NOT_REACHED(); return 0; }
-
     // Starts a one-shot cryptographic operation which can complete either
     // synchronously, or asynchronously.
     //