Update plugin to handle new style rules for virtual annotations.

tools/clang/plugins/tests/virtual_specifiers.txt

Index: tools/clang/plugins/tests/virtual_specifiers.txt
diff --git a/tools/clang/plugins/tests/virtual_specifiers.txt b/tools/clang/plugins/tests/virtual_specifiers.txt
new file mode 100644
index 0000000000000000000000000000000000000000..4dfe2a5ec5a688bc36e73a9f65efaf2783bb0232
--- /dev/null
+++ b/tools/clang/plugins/tests/virtual_specifiers.txt
@@ -0,0 +1,51 @@
+virtual_specifiers.cpp:32:21: warning: [chromium-style] Overriding method must be marked with 'override' or 'final'.
+  ~MissingOverride() {}
+                    ^
+                     override
+virtual_specifiers.cpp:33:11: warning: [chromium-style] Overriding method must be marked with 'override' or 'final'.
+  void F() {}
+          ^
+           override
+virtual_specifiers.cpp:39:3: warning: [chromium-style] 'virtual' is redundant; 'override' implies 'virtual'.
+  virtual ~VirtualAndOverride() OVERRIDE {}
+  ^~~~~~~~
+virtual_specifiers.cpp:40:3: warning: [chromium-style] 'virtual' is redundant; 'override' implies 'virtual'.
+  virtual void F() OVERRIDE {}
+  ^~~~~~~~
+virtual_specifiers.cpp:45:3: warning: [chromium-style] 'virtual' is redundant; 'final' implies 'virtual'.
+  virtual ~VirtualAndFinal() FINAL {}
+  ^~~~~~~~
+virtual_specifiers.cpp:46:3: warning: [chromium-style] 'virtual' is redundant; 'final' implies 'virtual'.
+  virtual void F() FINAL {}
+  ^~~~~~~~
+virtual_specifiers.cpp:51:3: warning: [chromium-style] 'virtual' is redundant; 'override' implies 'virtual'.
+  virtual ~VirtualAndOverrideFinal() OVERRIDE FINAL {}
+  ^~~~~~~~
+virtual_specifiers.cpp:51:38: warning: [chromium-style] 'override' is redundant; 'final' implies 'override'.
+  virtual ~VirtualAndOverrideFinal() OVERRIDE FINAL {}
+                                     ^~~~~~~~~
+virtual_specifiers.cpp:6:18: note: expanded from macro 'OVERRIDE'
+#define OVERRIDE override
+                 ^
+virtual_specifiers.cpp:52:3: warning: [chromium-style] 'virtual' is redundant; 'override' implies 'virtual'.
+  virtual void F() OVERRIDE FINAL {}
+  ^~~~~~~~
+virtual_specifiers.cpp:52:20: warning: [chromium-style] 'override' is redundant; 'final' implies 'override'.
+  virtual void F() OVERRIDE FINAL {}
+                   ^~~~~~~~~
+virtual_specifiers.cpp:6:18: note: expanded from macro 'OVERRIDE'
+#define OVERRIDE override
+                 ^
+virtual_specifiers.cpp:57:23: warning: [chromium-style] 'override' is redundant; 'final' implies 'override'.
+  ~OverrideAndFinal() OVERRIDE FINAL {}
+                      ^~~~~~~~~
+virtual_specifiers.cpp:6:18: note: expanded from macro 'OVERRIDE'
+#define OVERRIDE override
+                 ^
+virtual_specifiers.cpp:58:12: warning: [chromium-style] 'override' is redundant; 'final' implies 'override'.
+  void F() OVERRIDE FINAL {}
+           ^~~~~~~~~
+virtual_specifiers.cpp:6:18: note: expanded from macro 'OVERRIDE'
+#define OVERRIDE override
+                 ^
+12 warnings generated.