Update plugin to handle new style rules for virtual annotations.

tools/clang/plugins/tests/virtual_dtor_specifiers.txt

Index: tools/clang/plugins/tests/virtual_dtor_specifiers.txt
diff --git a/tools/clang/plugins/tests/virtual_dtor_specifiers.txt b/tools/clang/plugins/tests/virtual_dtor_specifiers.txt
new file mode 100644
index 0000000000000000000000000000000000000000..d60fec40ca9fa3e7d78afc996205c4c43d72e2c3
--- /dev/null
+++ b/tools/clang/plugins/tests/virtual_dtor_specifiers.txt
@@ -0,0 +1,26 @@
+virtual_dtor_specifiers.cpp:28:29: warning: [chromium-style] Overriding method must be marked with override or final.
+  virtual ~MissingOverride() {}
+                            ^
+                             override
+virtual_dtor_specifiers.cpp:34:3: warning: [chromium-style] virtual is redundant; 'override' implies virtual.
+  virtual ~VirtualAndOverride() OVERRIDE {}
+  ^~~~~~~~
+virtual_dtor_specifiers.cpp:39:3: warning: [chromium-style] virtual is redundant; 'final' implies virtual.
+  virtual ~VirtualAndFinal() FINAL {}
+  ^~~~~~~~
+virtual_dtor_specifiers.cpp:44:3: warning: [chromium-style] virtual is redundant; 'override' implies virtual.
+  virtual ~VirtualAndOverrideFinal() OVERRIDE FINAL {}
+  ^~~~~~~~
+virtual_dtor_specifiers.cpp:44:38: warning: [chromium-style] 'override' is redundant; 'final' implies 'override'.
+  virtual ~VirtualAndOverrideFinal() OVERRIDE FINAL {}
+                                     ^~~~~~~~~
+virtual_dtor_specifiers.cpp:5:18: note: expanded from macro 'OVERRIDE'
+#define OVERRIDE override
+                 ^
+virtual_dtor_specifiers.cpp:49:23: warning: [chromium-style] 'override' is redundant; 'final' implies 'override'.
+  ~OverrideAndFinal() OVERRIDE FINAL {}
+                      ^~~~~~~~~
+virtual_dtor_specifiers.cpp:5:18: note: expanded from macro 'OVERRIDE'
+#define OVERRIDE override
+                 ^
+6 warnings generated.