Android: Fix emulator tool path

In cases where the obsolete "Android SDK Tools" package is installed
in addition to the "Android SDK Command-line Tools", the older
emulator launcher is called. One reason for that is that the obsolete
package has a higher version number than the new one.

This change resorts to checking the existence of the new emulator
executable and falls back to the old one.

Fixes: QTCREATORBUG-28196
Change-Id: I753e0901334a87314a2c8c70fbc69e55dffc500c
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/android/androidconfigurations.cpp

@@ -471,10 +471,12 @@ FilePath AndroidConfig::adbToolPath() const
 
 FilePath AndroidConfig::emulatorToolPath() const
 {
-    QString relativePath = "emulator/emulator";
-    if (sdkToolsVersion() < QVersionNumber(25, 3, 0) && preCmdlineSdkToolsInstalled())
-        relativePath = "tools/emulator";
-    return m_sdkLocation / (relativePath + QTC_HOST_EXE_SUFFIX);
+    const FilePath emulatorFile = m_sdkLocation.pathAppended("emulator/emulator")
+                                      .withExecutableSuffix();
+    if (emulatorFile.exists())
+        return emulatorFile;
+
+    return m_sdkLocation.pathAppended("tools/emulator").withExecutableSuffix();
 }
 
 FilePath AndroidConfig::sdkManagerToolPath() const