[TextInputLayout] Counter label is invisible if TextInputLayout height is anything but 'wrap_content'

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**Description:** When enabling the "counter" helper text, the counter label itself isn't visible if the `TextInputLayout` has a static height; It's only visible if the `TextInputLayout` height is `wrap_content`.

**Expected behavior:** I expect that the counter label would be visible regardless of the height of the text field.

I'd be happy to try and dig in and fix this/submit a PR! Just want to clarify if this is expected behavior or not; I don't see much in the material spec. about large/multi-line text fields 🤷‍♂️

**Source code:** Below are some screenshots of a layout where I'm testing this.

I have two `TextInputLayout` fields aligned vertically. The counter is enabled on both, and the max. counter length is set to 5. The top field ("Friends email address") has its height set to `wrap_content` in both examples. The bottom field ("Add message") has its height as `wrap_content` in the first example, and a static height (`90dp`) in the second example.

The counter seems to work in both cases (field color is the correct error color when the text length is > counter max. length); the counter label is just hidden (height of 0) in the bottom example.

**Example 1** (IDs, styles and other attributes omitted)
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**Example 2** (IDs, styles and other attributes omitted)
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**Android API version:** Android 10

**Material Library version:** Tested on `1.1.0` and `1.2.0-beta01`

**Device:** Samsung S9 (SM-G960U1)

To help us triage faster, please check to make sure you are using the [latest version](https://github.com/material-components/material-components-android/releases) of the library.

We also happily accept [pull requests](https://github.com/material-components/material-components-android/pulls).

Start with the TextInputLayout counter behavior and reproduce the issue using the two XML layouts in the report, comparing wrap_content with a fixed 90dp height. Trace how the counter label is laid out and add a regression test for a fixed-height TextInputLayout. Done means the counter remains visible when the field height is fixed.

Written by the indexing model from the issue text.