[2.1] Invalid block type "Magento\Braintree\Block\Paypal\Button"

[acharrex]

Steps to reproduce

1. Install Magento from develop branch.
2. Add a product to the cart
3. Go to the shopping cart

Expected result

1. Shopping cart page shown without any error

Actual result

1. Error message appears: "Invalid block type: Magento\Braintree\Block\Paypal\Button"

[acharrex]

Fix:
Rename the folder "vendor/magento/module-braintree/Block/PayPal" by "vendor/magento/module-braintree/Block/Paypal".

[YevSent]

The same problem as in #5535.
The Magento repo contains the correct folder name https://github.com/magento/magento2/tree/develop/app/code/Magento/Braintree/Block. Try to clear your vendor directory and composer cache, and run compose update again.