[FlexLayout] Labels with word wrap do not seem to auto calculate height correctly

Description

Text can be cut off/truncated when there are several FlexLayout's with Labels, filling a StackLayout

In the example below, 8 lines of text are assigned to the label, but when rendered to the screen (only tested on Android phone) only 5 lines are displayed before truncation

<StackLayout VerticalOptions="FillAndExpand" Padding="70,5,0,0">
            <FlexLayout Direction="Row" Wrap="Wrap">
                <Label FlexLayout.Grow="1" FlexLayout.Basis="100" Text="NOTES"/>
                <Label FlexLayout.Grow="2" FlexLayout.Basis="150"
                    Text="1This is a test to see if the word wrap will not cut off. 
                          2This is a test to see if the word wrap will not cut off. 
                          3This is a test to see if the word wrap will not cut off. 
                          4This is a test to see if the word wrap will not cut off. 
                          5This is a test to see if the word wrap will not cut off. 
                          6This is a test to see if the word wrap will not cut off. 
                          7This is a test to see if the word wrap will not cut off. 
                          8This is a test to see if the word wrap will not cut off. "/>
            </FlexLayout>
            <FlexLayout Direction="Row" Wrap="Wrap">
                <Label FlexLayout.Grow="1" FlexLayout.Basis="100" Text="NOTES"/>
                <Label FlexLayout.Grow="2" FlexLayout.Basis="150"
                    Text="1This is a test to see if the word wrap will not cut off. 
                          2This is a test to see if the word wrap will not cut off. 
                          3This is a test to see if the word wrap will not cut off. 
                          4This is a test to see if the word wrap will not cut off. 
                          5This is a test to see if the word wrap will not cut off. 
                          6This is a test to see if the word wrap will not cut off. 
                          7This is a test to see if the word wrap will not cut off. 
                          8This is a test to see if the word wrap will not cut off. "/>
            </FlexLayout>

(copy/paste FlexLayout several more times)
  ...

Steps to Reproduce

• See attached Repo.zip

Expected Behavior

Display all text within the top-most FlexLayouts

Actual Behavior

Text is being truncated in each label. (in order to fit more controls on the screen?)

Basic Information

• Version with issue:
  • Xamarin Form 3.4.0.1009999

Screenshots

Reproduction Link

• Repo.zip - https://github.com/xamarin/Xamarin.Forms/files/2746948/Repo.zip
• MainPage.xaml Gist - https://gist.github.com/mattregul/edb5219149afa4136045b87ad606d9aa
• Xamarin Forum Post - https://forums.xamarin.com/discussion/145900/long-label-with-word-wrap-doesnt-seem-to-auto-calculate-height-correctly