Adopt same code for host-test version of esp_try_delay.

Fix in-source specification for the main `esp_try_delay`.

cores/esp8266/coredecls.h

@@ -51,10 +51,11 @@ inline void esp_suspend(T&& blocked) {
     } while (blocked());
 }
 
-// Try to delay for timeout_ms relative to start_ms. Returns false if the delayed task
-// is asynchronously resumed before the timeout is reached.
-// Also returns false if intvl_ms have expired during the active call.
-// Otherwise return true to indicate the timeout_ms have completely expired.
+// Try to delay until timeout_ms has expired since start_ms.
+// Returns true if timeout_ms has completely expired on entry.
+// Otherwise returns false after delaying for the relative
+// remainder of timeout_ms, or an absolute intvl_ms, whichever is shorter.
+// The delay may be asynchronously cancelled, before that timeout is reached.
 bool esp_try_delay(const uint32_t start_ms, const uint32_t timeout_ms, const uint32_t intvl_ms);
 
 // This overload of esp_delay() delays for a duration of at most timeout_ms milliseconds.

tests/host/common/Arduino.cpp

@@ -72,13 +72,11 @@ extern "C" void esp_delay (unsigned long ms)
 }
 
 bool esp_try_delay(const uint32_t start_ms, const uint32_t timeout_ms, const uint32_t intvl_ms) {
-    decltype(millis()) expired;
-
-    if ((expired = millis() - start_ms) >= timeout_ms) {
+    uint32_t expired = millis() - start_ms;
+    if (expired >= timeout_ms) {
         return true;
     }
-    const auto remaining = timeout_ms - expired;
-    esp_delay(remaining <= intvl_ms ? remaining : intvl_ms);
+    esp_delay(std::min((timeout_ms - expired), intvl_ms));
     return false;
 }