adbd: demote CHECKs to warning logs.

It seems like we don't actually always get these events in order, so
demote them to a log and restart the connection instead of aborting.

Bug: http://b/129464137
Test: mma
Change-Id: I7dffbf62f9dea665cf9f9f9e1bd18d444b6905ec
diff --git a/daemon/usb.cpp b/daemon/usb.cpp
index 14cdb69..8c33ca5 100644
--- a/daemon/usb.cpp
+++ b/daemon/usb.cpp
@@ -304,33 +304,57 @@
 
                 switch (event.type) {
                     case FUNCTIONFS_BIND:
-                        CHECK(!bound) << "received FUNCTIONFS_BIND while already bound?";
-                        CHECK(!enabled) << "received FUNCTIONFS_BIND while already enabled?";
-                        bound = true;
+                        if (bound) {
+                            LOG(WARNING) << "received FUNCTIONFS_BIND while already bound?";
+                            running = false;
+                        }
 
+                        if (enabled) {
+                            LOG(WARNING) << "received FUNCTIONFS_BIND while already enabled?";
+                            running = false;
+                        }
+
+                        bound = true;
                         break;
 
                     case FUNCTIONFS_ENABLE:
-                        CHECK(bound) << "received FUNCTIONFS_ENABLE while not bound?";
-                        CHECK(!enabled) << "received FUNCTIONFS_ENABLE while already enabled?";
-                        enabled = true;
+                        if (!bound) {
+                            LOG(WARNING) << "received FUNCTIONFS_ENABLE while not bound?";
+                            running = false;
+                        }
 
+                        if (enabled) {
+                            LOG(WARNING) << "received FUNCTIONFS_ENABLE while already enabled?";
+                            running = false;
+                        }
+
+                        enabled = true;
                         StartWorker();
                         break;
 
                     case FUNCTIONFS_DISABLE:
-                        CHECK(bound) << "received FUNCTIONFS_DISABLE while not bound?";
-                        CHECK(enabled) << "received FUNCTIONFS_DISABLE while not enabled?";
-                        enabled = false;
+                        if (!bound) {
+                            LOG(WARNING) << "received FUNCTIONFS_DISABLE while not bound?";
+                        }
 
+                        if (!enabled) {
+                            LOG(WARNING) << "received FUNCTIONFS_DISABLE while not enabled?";
+                        }
+
+                        enabled = false;
                         running = false;
                         break;
 
                     case FUNCTIONFS_UNBIND:
-                        CHECK(!enabled) << "received FUNCTIONFS_UNBIND while still enabled?";
-                        CHECK(bound) << "received FUNCTIONFS_UNBIND when not bound?";
-                        bound = false;
+                        if (enabled) {
+                            LOG(WARNING) << "received FUNCTIONFS_UNBIND while still enabled?";
+                        }
 
+                        if (!bound) {
+                            LOG(WARNING) << "received FUNCTIONFS_UNBIND when not bound?";
+                        }
+
+                        bound = false;
                         running = false;
                         break;
                 }