image_picker: Use FileProvider subclass to avoid collisions (#716)

packages/image_picker/android/src/main/AndroidManifest.xml

diff --git a/packages/image_picker/android/src/main/AndroidManifest.xml b/packages/image_picker/android/src/main/AndroidManifest.xml
index 22e6e62..dba1508 100755
--- a/packages/image_picker/android/src/main/AndroidManifest.xml
+++ b/packages/image_picker/android/src/main/AndroidManifest.xml
@@ -6,7 +6,7 @@
 
     <application>
         <provider
-            android:name="android.support.v4.content.FileProvider"
+            android:name="io.flutter.plugins.imagepicker.ImagePickerFileProvider"
             android:authorities="${applicationId}.flutter.image_provider"
             android:exported="false"
             android:grantUriPermissions="true">

packages/image_picker/android/src/main/java/io/flutter/plugins/imagepicker/ImagePickerFileProvider.java

diff --git a/packages/image_picker/android/src/main/java/io/flutter/plugins/imagepicker/ImagePickerFileProvider.java b/packages/image_picker/android/src/main/java/io/flutter/plugins/imagepicker/ImagePickerFileProvider.java
new file mode 100644
index 0000000..92ec194
--- /dev/null
+++ b/packages/image_picker/android/src/main/java/io/flutter/plugins/imagepicker/ImagePickerFileProvider.java
@@ -0,0 +1,10 @@
+package io.flutter.plugins.imagepicker;
+
+import android.support.v4.content.FileProvider;
+
+/**
+ * Providing a custom {@code FileProvider} prevents manifest {@code <provider>} name collisions.
+ *
+ * <p>See https://developer.android.com/guide/topics/manifest/provider-element.html for details.
+ */
+public class ImagePickerFileProvider extends FileProvider {}