Copter: consolidate throw mode state into structure

ArduCopter/Copter.h

@@ -274,14 +274,6 @@ private:
         uint32_t start_ms;
     } takeoff_state;
 
-    // throw mode state
-    struct {
-        ThrowModeStage stage;
-        ThrowModeStage prev_stage;
-        uint32_t last_log_ms;
-        bool nextmode_attempted;
-    } throw_state = {Throw_Disarmed, Throw_Disarmed, 0, false};
-
     uint32_t precland_last_update_ms;
 
     // altitude below which we do no navigation in auto takeoff
@@ -410,9 +402,15 @@ private:
     // Flip
     Vector3f flip_orig_attitude;         // original copter attitude before flip
 
-    // Throw
-    uint32_t throw_free_fall_start_ms = 0;  // system time free fall was detected
-    float throw_free_fall_start_velz = 0.0f;// vertical velocity when free fall was detected
+    // throw mode state
+    struct {
+        ThrowModeStage stage;
+        ThrowModeStage prev_stage;
+        uint32_t last_log_ms;
+        bool nextmode_attempted;
+        uint32_t free_fall_start_ms;    // system time free fall was detected
+        float free_fall_start_velz;     // vertical velocity when free fall was detected
+    } throw_state = {Throw_Disarmed, Throw_Disarmed, 0, false, 0, 0.0f};
 
     // Battery Sensors
     AP_BattMonitor battery;

ArduCopter/control_throw.cpp

@@ -234,13 +234,13 @@ bool Copter::throw_detected()
     bool possible_throw_detected = (free_falling || high_speed) && changing_height && no_throw_action;
 
     // Record time and vertical velocity when we detect the possible throw
-    if (possible_throw_detected && ((AP_HAL::millis() - throw_free_fall_start_ms) > 500)) {
-        throw_free_fall_start_ms = AP_HAL::millis();
-        throw_free_fall_start_velz = inertial_nav.get_velocity().z;
+    if (possible_throw_detected && ((AP_HAL::millis() - throw_state.free_fall_start_ms) > 500)) {
+        throw_state.free_fall_start_ms = AP_HAL::millis();
+        throw_state.free_fall_start_velz = inertial_nav.get_velocity().z;
     }
 
     // Once a possible throw condition has been detected, we check for 2.5 m/s of downwards velocity change in less than 0.5 seconds to confirm
-    bool throw_condition_confirmed = ((AP_HAL::millis() - throw_free_fall_start_ms < 500) && ((inertial_nav.get_velocity().z - throw_free_fall_start_velz) < -250.0f));
+    bool throw_condition_confirmed = ((AP_HAL::millis() - throw_state.free_fall_start_ms < 500) && ((inertial_nav.get_velocity().z - throw_state.free_fall_start_velz) < -250.0f));
 
     // start motors and enter the control mode if we are in continuous freefall
     if (throw_condition_confirmed) {