cmake: use ALLOW_MEMORY_GROWTH=1 for web examples

The default memory limit for emscripten applications is 16 mergabytes,
which might be to little for some examples, especially given that the
resources are also included in that limit.

Normally, using this option disables some asm.js optimizations, but
there's no such cost for WebAssembly.

examples/CMakeLists.txt

@@ -56,7 +56,10 @@ if(${PLATFORM} MATCHES "Android")
 
 elseif(${PLATFORM} MATCHES "Web")
   set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Os -s USE_GLFW=3 -s ASSERTIONS=1 -s WASM=1 -s EMTERPRETIFY=1 -s EMTERPRETIFY_ASYNC=1")
+  # Since WASM is used, ALLOW_MEMORY_GROWTH has no extra overheads
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -s ALLOW_MEMORY_GROWTH=1 --no-heap-copy")
   set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} --shell-file ${CMAKE_SOURCE_DIR}/templates/web_shell/shell.html")
+
   set(OUTPUT_EXT ".html")
 
 endif()