Change DebugCanvas API to not encourage memory leaks

platform_tools/nacl/src/nacl_debugger.cpp

Index: platform_tools/nacl/src/nacl_debugger.cpp
diff --git a/platform_tools/nacl/src/nacl_debugger.cpp b/platform_tools/nacl/src/nacl_debugger.cpp
index b80dde093845a612b79d9105417bb4ec0635fd80..e7e26b812925a4ddd2ba8a157670f6e42868dc2b 100644
--- a/platform_tools/nacl/src/nacl_debugger.cpp
+++ b/platform_tools/nacl/src/nacl_debugger.cpp
@@ -76,11 +76,10 @@ public:
                 picture->unref();
 
                 // Set up the command list.
-                SkTArray<SkString>* commands = fDebugger.getDrawCommandsAsStrings();
                 PostMessage("ClearCommands");
-                for (int i = 0; i < commands->count(); ++i) {
+                for (int i = 0; i < fDebugger.getSize(); ++i) {
                     SkString addCommand("AddCommand:");
-                    addCommand.append((*commands)[i]);
+                    addCommand.append(fDebugger.getDrawCommandAt(i)->toString());
                     PostMessage(addCommand.c_str());
                 }
                 PostMessage("UpdateCommands");