Add second batch of fuzzers for libutils

This adds fuzzers for:
- CallStack
- Looper
- LruCache
- Printer
- ProcessCallStack
- PropertyMap
- RWLock
- RefBase
- StopWatch.
Test: Ran each fuzzer for 10 minutes. Rough coverage est. (likely far below actual value): 10.97%

Signed-off-by: Dylan Katz <dylan.katz@leviathansecurity.com>
Change-Id: I2f9f35c18b13338c282fb7f9c3ea4099ecb2c56f
diff --git a/libutils/StopWatch_fuzz.cpp b/libutils/StopWatch_fuzz.cpp
new file mode 100644
index 0000000..63d8a28
--- /dev/null
+++ b/libutils/StopWatch_fuzz.cpp
@@ -0,0 +1,45 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "fuzzer/FuzzedDataProvider.h"
+#include "utils/StopWatch.h"
+
+static constexpr int MAX_OPERATIONS = 100;
+static constexpr int MAX_NAME_LEN = 2048;
+
+static const std::vector<std::function<void(android::StopWatch)>> operations = {
+        [](android::StopWatch stopWatch) -> void { stopWatch.reset(); },
+        [](android::StopWatch stopWatch) -> void { stopWatch.lap(); },
+        [](android::StopWatch stopWatch) -> void { stopWatch.elapsedTime(); },
+        [](android::StopWatch stopWatch) -> void { stopWatch.name(); },
+};
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+    FuzzedDataProvider dataProvider(data, size);
+    std::string nameStr = dataProvider.ConsumeRandomLengthString(MAX_NAME_LEN);
+    int clockVal = dataProvider.ConsumeIntegral<int>();
+    android::StopWatch stopWatch = android::StopWatch(nameStr.c_str(), clockVal);
+    std::vector<uint8_t> opsToRun = dataProvider.ConsumeRemainingBytes<uint8_t>();
+    int opsRun = 0;
+    for (auto it : opsToRun) {
+        if (opsRun++ >= MAX_OPERATIONS) {
+            break;
+        }
+        it = it % operations.size();
+        operations[it](stopWatch);
+    }
+    return 0;
+}