<h2 dir="auto">Steps to Reproduce</h2>
<p dir="auto">Create simple Scaffold with AppBar and endDrawer. Make drawer visible. See that under transparent part of the view, in appBar, back button shows up. It might be related with <a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="268139019" data-permission-text="Title is private" data-url="https://github.com/flutter/flutter/issues/12691" data-hovercard-type="issue" data-hovercard-url="/flutter/flutter/issues/12691/hovercard" href="https://github.com/flutter/flutter/issues/12691">#12691</a> issue.</p>
<p dir="auto"><a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/16545480/34540904-9589b0e8-f0d6-11e7-9178-79874cba3bc7.jpg"><img src="https://user-images.githubusercontent.com/16545480/34540904-9589b0e8-f0d6-11e7-9178-79874cba3bc7.jpg" alt="back_button_issue" style="max-width: 100%;"></a></p>
<h2 dir="auto">Logs</h2>
<h2 dir="auto">Flutter Doctor</h2>
<p dir="auto">[✓] Flutter (on Linux, locale en_US.UTF-8, channel alpha)<br>
• Flutter at /home/kamil/Flutter<br>
• Framework revision <a class="commit-link" data-hovercard-type="commit" data-hovercard-url="https://github.com/flutter/flutter/commit/8f65fec5f5f7d7afbb0965f4a44bdb330a28fb19/hovercard" href="https://github.com/flutter/flutter/commit/8f65fec5f5f7d7afbb0965f4a44bdb330a28fb19"><tt>8f65fec</tt></a> (3 weeks ago), 2017-12-12 09:50:14 -0800<br>
• Engine revision <a class="commit-link" data-hovercard-type="commit" data-hovercard-url="https://github.com/flutter/flutter/commit/edaecdc8b8098f20512c23745b9d0b135a8ee56d/hovercard" href="https://github.com/flutter/flutter/commit/edaecdc8b8098f20512c23745b9d0b135a8ee56d"><tt>edaecdc</tt></a><br>
• Tools Dart version 1.25.0-dev.11.0<br>
• Engine Dart version 2.0.0-edge.d8ae797298c3a6cf8dc9f4558707bd2672224d3e</p>
<p dir="auto">[✓] Android toolchain - develop for Android devices (Android SDK 26.0.2)<br>
• Android SDK at /home/kamil/Programs/Android/<br>
• Android NDK at /home/kamil/Programs/Android/ndk-bundle<br>
• Platform android-26, build-tools 26.0.2<br>
• ANDROID_HOME = /home/kamil/Programs/Android/<br>
• Java binary at: /home/kamil/Programs/android-studio/jre/bin/java<br>
• Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b01)</p>
<p dir="auto">[✓] Android Studio (version 3.0)<br>
• Android Studio at /home/kamil/Programs/android-studio<br>
• Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b01)</p>
<p dir="auto">[✓] Connected devices<br>
• Android SDK built for x86 • emulator-5554 • android-x86 • Android 8.0.0 (API 26) (emulator)</p>
<h2 dir="auto">Steps to Reproduce</h2>
<ol dir="auto">
<li>Add an <code class="notranslate">appBar</code> with a <code class="notranslate">title</code> and <code class="notranslate">endDrawer</code> to a <code class="notranslate">Scaffold</code> in a LTR language (English in my case).</li>
<li>Observe the <code class="notranslate">AppBar</code>. No back button.</li>
<li>Open the <code class="notranslate">endDrawer</code></li>
<li>Observe the <code class="notranslate">AppBar</code>. Back Button appears.</li>
</ol>
<p dir="auto">Not an end of the world bug by any means, but overall it looks a bit weird / causes a visual flash in the UI as the Drawer animates in smoothly and then the back button pops in all of a sudden. In addition, it can't be tapped because it's underneath the Drawer layer, so it appears to lack functional value for being there.</p>
<p dir="auto">Might make sense to simply not show the back button in response to a Drawer being opened? Not sure what other ramifications that would have...</p>
<p dir="auto">Thanks for your time :)</p>
<h2 dir="auto">Screenshot</h2>
<p dir="auto"><a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/126604/34038468-bb376c08-e18c-11e7-9886-b08b6089e209.png"><img src="https://user-images.githubusercontent.com/126604/34038468-bb376c08-e18c-11e7-9886-b08b6089e209.png" alt="screenshot_1513334416" style="max-width: 100%;"></a></p>
<h2 dir="auto">Flutter Doctor</h2>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="[✓] Flutter (on Mac OS X 10.13.2 17C88, locale en-US, channel alpha)
    • Flutter at /Users/phillywiggins/lab/flutter
    • Framework revision 8f65fec5f5 (3 days ago), 2017-12-12 09:50:14 -0800
    • Engine revision edaecdc8b8
    • Tools Dart version 1.25.0-dev.11.0
    • Engine Dart version 2.0.0-edge.d8ae797298c3a6cf8dc9f4558707bd2672224d3e

[✓] Android toolchain - develop for Android devices (Android SDK 26.0.2)
    • Android SDK at /Users/phillywiggins/Library/Android/sdk
    • Android NDK at /Users/phillywiggins/Library/Android/sdk/ndk-bundle
    • Platform android-26, build-tools 26.0.2
    • ANDROID_HOME = /Users/phillywiggins/Library/Android/sdk
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b08)

[✓] iOS toolchain - develop for iOS devices (Xcode 9.2)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 9.2, Build version 9C40b
    • ios-deploy 1.9.2
    • CocoaPods version 1.3.1

[✓] Android Studio (version 3.0)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b08)

[✓] IntelliJ IDEA Community Edition (version 2017.3.1)
    • Flutter plugin version 20.0.3
    • Dart plugin version 173.3942.31

[✓] Connected devices
    • Android SDK built for x86 • emulator-5554 • android-x86 • Android 8.0.0 (API 26) (emulator)"><pre class="notranslate"><code class="notranslate">[✓] Flutter (on Mac OS X 10.13.2 17C88, locale en-US, channel alpha)
    • Flutter at /Users/phillywiggins/lab/flutter
    • Framework revision 8f65fec5f5 (3 days ago), 2017-12-12 09:50:14 -0800
    • Engine revision edaecdc8b8
    • Tools Dart version 1.25.0-dev.11.0
    • Engine Dart version 2.0.0-edge.d8ae797298c3a6cf8dc9f4558707bd2672224d3e

[✓] Android toolchain - develop for Android devices (Android SDK 26.0.2)
    • Android SDK at /Users/phillywiggins/Library/Android/sdk
    • Android NDK at /Users/phillywiggins/Library/Android/sdk/ndk-bundle
    • Platform android-26, build-tools 26.0.2
    • ANDROID_HOME = /Users/phillywiggins/Library/Android/sdk
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b08)

[✓] iOS toolchain - develop for iOS devices (Xcode 9.2)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 9.2, Build version 9C40b
    • ios-deploy 1.9.2
    • CocoaPods version 1.3.1

[✓] Android Studio (version 3.0)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b08)

[✓] IntelliJ IDEA Community Edition (version 2017.3.1)
    • Flutter plugin version 20.0.3
    • Dart plugin version 173.3942.31

[✓] Connected devices
    • Android SDK built for x86 • emulator-5554 • android-x86 • Android 8.0.0 (API 26) (emulator)
</code></pre></div>