Fixed current and potential bugs caught by Coverity

Change-Id: I9f9d09dc797ffea062eeb49c881be1d5acb63d7b

wpilibc/shared/include/Commands/CommandGroupEntry.h

@@ -22,7 +22,7 @@ class CommandGroupEntry {
   CommandGroupEntry(Command *command, Sequence state, double timeout = -1.0);
   bool IsTimedOut() const;
 
-  double m_timeout;
+  double m_timeout = -1.0;
   Command *m_command = nullptr;
   Sequence m_state = kSequence_InSequence;
 };

wpilibc/shared/include/LiveWindow/LiveWindow.h

@@ -11,7 +11,7 @@
 struct LiveWindowComponent {
   std::string subsystem;
   std::string name;
-  bool isSensor;
+  bool isSensor = false;
 
   LiveWindowComponent() = default;
   LiveWindowComponent(std::string subsystem, std::string name, bool isSensor) {

wpilibc/shared/include/PIDController.h

@@ -93,7 +93,6 @@ class PIDController : public LiveWindowSendable,
   float m_minimumInput = 0;   // minimum input - limit setpoint to this
   bool m_continuous = false;      // do the endpoints wrap around? eg. Absolute encoder
   bool m_enabled = false;  // is the pid controller enabled
-  bool m_destruct;    // should the calculate thread stop running
   float m_prevInput = 0;  // the prior sensor input (used to compute velocity)
   double m_totalError = 0;  // the sum of the errors for use in the integral calc
   enum {
@@ -105,7 +104,7 @@ class PIDController : public LiveWindowSendable,
   // the percetage or absolute error that is considered on target.
   float m_tolerance = 0.05;
   float m_setpoint = 0;
-  float m_error;
+  float m_error = 0;
   float m_result = 0;
   float m_period;
 

wpilibc/shared/include/SensorBase.h

@@ -56,5 +56,5 @@ class SensorBase : public ErrorBase {
 
  private:
   static SensorBase* m_singletonList;
-  SensorBase* m_nextSingleton;
+  SensorBase* m_nextSingleton = nullptr;
 };