Add missing requireGlContext

Change-Id: I7100e5e9986f502f66a23ecea07a6057522c43ac
diff --git a/libs/hwui/renderthread/CanvasContext.cpp b/libs/hwui/renderthread/CanvasContext.cpp
index 524ee62dd..f5d4f8b 100644
--- a/libs/hwui/renderthread/CanvasContext.cpp
+++ b/libs/hwui/renderthread/CanvasContext.cpp
@@ -260,6 +260,7 @@
     // No context means nothing to free
     if (!thread.eglManager().hasEglContext()) return;
 
+    thread.eglManager().requireGlContext();
     if (level >= TRIM_MEMORY_COMPLETE) {
         Caches::getInstance().flush(Caches::kFlushMode_Full);
         thread.eglManager().destroy();