Free memory allocated by bitmap obj

Author: gamblor21

shared-module/displayio/Bitmap.c

@@ -50,6 +50,9 @@ void common_hal_displayio_bitmap_construct_from_buffer(displayio_bitmap_t *self,
     self->stride = stride(width, bits_per_value);
     if (!data) {
         data = m_malloc(self->stride * height * sizeof(uint32_t), false);
+        self->data_alloc = true;
+    } else {
+        self->data_alloc = false;
     }
     self->data = data;
     self->read_only = read_only;
@@ -80,6 +83,9 @@ void common_hal_displayio_bitmap_construct_from_buffer(displayio_bitmap_t *self,
 }
 
 void common_hal_displayio_bitmap_deinit(displayio_bitmap_t *self) {
+    if (self->data_alloc) {
+        m_free(self->data);
+    }
     self->data = NULL;
 }
 

shared-module/displayio/Bitmap.h

@@ -45,6 +45,7 @@ typedef struct {
     displayio_area_t dirty_area;
     uint16_t bitmask;
     bool read_only;
+    bool data_alloc; // did bitmap allocate data or someone else
 } displayio_bitmap_t;
 
 void displayio_bitmap_finish_refresh(displayio_bitmap_t *self);