Build wallet with Android NDK

src/crypto/CMakeLists.txt

@@ -89,3 +89,14 @@ if (ARM)
       PROPERTY COMPILE_DEFINITIONS "NO_OPTIMIZED_MULTIPLY_ON_ARM")
   endif()
 endif()
+
+# Because of the way Qt works on android with JNI, the code does not live in the main android thread
+# So this code runs with a 1 MB default stack size. 
+# This will force the use of the heap for the allocation of the scratchpad
+if (ANDROID)
+  if( BUILD_GUI_DEPS )
+    add_definitions(-DFORCE_USE_HEAP=1)
+  endif()
+endif()
+
+