core: don't erase passphrase on ClearSession

core/src/apps/common/cache.py

@@ -56,9 +56,7 @@ def set_passphrase(passphrase):
     _cached_passphrase_fprint = _compute_state(b"FPRINT", passphrase or "")[:4]
 
 
-def clear(skip_passphrase: bool = False):
+def clear(keep_passphrase: bool = False):
     set_seed(None)
-    if skip_passphrase:
-        set_passphrase("")
-    else:
+    if not keep_passphrase:
         set_passphrase(None)

core/src/apps/homescreen/__init__.py

@@ -32,7 +32,9 @@ def get_features():
 
 async def handle_Initialize(ctx, msg):
     if msg.state is None or msg.state != cache.get_state(prev_state=bytes(msg.state)):
-        cache.clear(msg.skip_passphrase)
+        cache.clear()
+        if msg.skip_passphrase:
+            cache.set_passphrase("")
     return get_features()
 
 
@@ -45,7 +47,7 @@ async def handle_Cancel(ctx, msg):
 
 
 async def handle_ClearSession(ctx, msg):
-    cache.clear()
+    cache.clear(keep_passphrase=True)
     return Success(message="Session cleared")