Add tests (and fix!) for known bad ICO files.

tests/BadIcoTest.cpp

+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "Resources.h"
+#include "Test.h"
+#include "SkBitmap.h"
+#include "SkImageDecoder.h"
+#include "SkOSFile.h"
+
+DEF_TEST(BadIco, reporter) {
+    const char* const badIcos [] = {
+        "sigabort_favicon.ico",
+        "sigsegv_favicon.ico",
+        "sigsegv_favicon_2.ico",
+    };
+
+    const char* badIcoFolder = "invalid_images";
+
+    SkString resourcePath = GetResourcePath(badIcoFolder);
+
+    SkBitmap bm;
+    for (size_t i = 0; i < SK_ARRAY_COUNT(badIcos); ++i) {
+        SkString fullPath = SkOSPath::Join(resourcePath.c_str(), badIcos[i]);
+        bool success = SkImageDecoder::DecodeFile(fullPath.c_str(), &bm);
+        // These files are invalid, and should not decode. More importantly,
+        // though, we reached here without crashing.
+        REPORTER_ASSERT(reporter, !success);
+    }
+}