Fix runtime error when using EMCC 1.39.5.

CMake/Modules/UrhoCommon.cmake

@@ -678,7 +678,9 @@ else ()
                 # (See https://github.com/kripken/emscripten/commit/3bc1f9f08b9f420680124af703c787244468cedc for more detail)
                 # Since version 1.37.28 emcc reduces default runtime exports, but we need "FS" so it needs to be explicitly requested now
                 # (See https://github.com/kripken/emscripten/commit/f2191c1223e8261bf45f4e27d2ba4d2e9d8b3341 for more detail)
-                set (CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -s EXTRA_EXPORTED_RUNTIME_METHODS=\"['Pointer_stringify']\" -s FORCE_FILESYSTEM=1")
+                # Since version 1.39.5 emcc disables deprecated find event target behavior by default; we revert the flag for now until the support is removed
+                # (See https://github.com/emscripten-core/emscripten/commit/948af470be12559367e7629f31cf7c841fbeb2a9#diff-291d81f9d42b322a89881b6d91f7a122 for more detail)
+                set (CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -s EXTRA_EXPORTED_RUNTIME_METHODS=\"['Pointer_stringify']\" -s FORCE_FILESYSTEM=1 -s DISABLE_DEPRECATED_FIND_EVENT_TARGET_BEHAVIOR=0")
                 set (CMAKE_C_FLAGS_RELEASE "-Oz -DNDEBUG")
                 set (CMAKE_CXX_FLAGS_RELEASE "-Oz -DNDEBUG")
                 # Remove variables to make the -O3 regalloc easier