[REQUIRED] Step 1: Describe your environment

• Xcode version: 11.3.1
• Firebase SDK version: 6.21.0
• Firebase Component: InAppMessaging
• Component version: 0.19.1
• Installation method: CocoaPods (cocoapods-rome plugin)

[REQUIRED] Step 2: Describe the problem

When building the framework I get the following error:

Undefined symbols for architecture armv7:
  "_OBJC_CLASS_$_GULAppEnvironmentUtil", referenced from:
      objc-class-ref in FIRInAppMessaging+Bootstrap.o
ld: symbol(s) not found for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Steps to reproduce:

What happened? How can we make the problem occur?
Unzip the file and run make (cocoapods-rome plugin must be installed to build).

InAppMessaging.zip