Add configuration system for core renderdoc module

* This allows persistent config storage and registering tweak variables that
  works independent of the UI's configuration.
* Config vars can be debug only, which means they will be compiled out in stable
  version releases. This allows for debug-logging tweaks that are available in
  all builds (including nightly builds) for diagnostic purposes, but have zero
  overhead in stable releases.
* Variables have a loose hierarchy defined with _ or . to separate nodes.

renderdoc/android/android.cpp

@@ -30,10 +30,15 @@
 #include "common/threading.h"
 #include "core/core.h"
 #include "core/remote_server.h"
+#include "core/settings.h"
 #include "replay/replay_driver.h"
 #include "strings/string_utils.h"
 #include "android_utils.h"
 
+RDOC_CONFIG(uint32_t, Android_MaxConnectTimeout, 30,
+            "Maximum time in seconds to try connecting to the target app before giving up. "
+            "Useful primarily for apps that take a very long time to start up.");
+
 namespace Android
 {
 void adbForwardPorts(uint16_t portbase, const rdcstr &deviceID, uint16_t jdwpPort, int pid,
@@ -1166,10 +1171,7 @@ ExecuteResult AndroidRemoteServer::ExecuteAndInject(const char *a, const char *w
 
     ret.status = ReplayStatus::InjectionFailed;
 
-    uint32_t elapsed = 0,
-             timeout =
-                 1000 *
-                 RDCMAX(5, atoi(RenderDoc::Inst().GetConfigSetting("MaxConnectTimeout").c_str()));
+    uint32_t elapsed = 0, timeout = 1000 * RDCMAX(5U, Android_MaxConnectTimeout);
     while(elapsed < timeout)
     {
       // Check if the target app has started yet and we can connect to it.