Add clang-tidy support for the CDM

Bug: 256230932
Change-Id: Id3fcf024cd7dcf95218876b81359d6418f5aa067

libwvdrmengine/cdm/metrics/include/metrics_collections.h

@@ -61,7 +61,6 @@
 
 namespace wvcdm {
 namespace metrics {
-namespace {
 // Short name definitions to ease AttributeHandler definitions.
 // Internal namespace to help simplify declarations.
 const int kErrorCodeFieldNumber =
@@ -91,7 +90,6 @@ const int kLicenseTypeFieldNumber =
     ::drm_metrics::Attributes::kLicenseTypeFieldNumber;
 const int kOemCryptoSignatureHashAlgorithmFieldNumber =
     ::drm_metrics::Attributes::kOemCryptoSignatureHashAlgorithmFieldNumber;
-}  // namespace
 
 // The maximum number of completed sessions that can be stored. More than this
 // will cause some metrics to be discarded.

libwvdrmengine/cdm/metrics/include/value_metric.h

@@ -39,8 +39,6 @@ void SetValue(drm_metrics::ValueMetric* value_proto, const T& value);
 template <typename T>
 class ValueMetric {
  public:
-  ValueMetric() {}
-
   // Record the value of the metric.
   void Record(const T& value) {
     std::unique_lock<std::mutex> lock(mutex_);
@@ -103,7 +101,7 @@ class ValueMetric {
  private:
   enum ValueState { kNone, kHasValue, kHasError };
 
-  T value_;
+  T value_ = T();
   int error_code_ = 0;
   ValueState state_ = kNone;