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- Do not show generic file handler (file handlers which can take any type of file such as types:["*"]) as a default task.
- All file handlers are shown in context menu and menu of the combobottuon.

BUG=414566
TEST=out/Release/browser_tests --gtest_filter=GenericTask/FileManagerBrowserTest.Test/*

Review URL: https://codereview.chromium.org/700023002

Cr-Commit-Position: refs/heads/master@{#302777}