update_engine: Reduce the generated file sizes in some unittests

It seems like the builders sometimes run out of space on temp dir and
the tests can't create the file with specific sizes they want. So, this
CL reduces the size needed so we don't hit this problem often (or at
all).

BUG=b:173189147
TEST=FEATURES=test GTEST_FILTER="*P2PManagerTest.MakeFileVisible*"  emerge-reef update_engine

Change-Id: I0a95fa3d0c50b8acdeb2dd059afc206d0e10c7d9
Reviewed-on: https://chromium-review.googlesource.com/c/aosp/platform/system/update_engine/+/2570177
Tested-by: Amin Hassani <ahassani@chromium.org>
Commit-Queue: Amin Hassani <ahassani@chromium.org>
Commit-Queue: Jae Hoon Kim <kimjae@chromium.org>
Auto-Submit: Amin Hassani <ahassani@chromium.org>
Reviewed-by: Jae Hoon Kim <kimjae@chromium.org>
diff --git a/cros/p2p_manager_unittest.cc b/cros/p2p_manager_unittest.cc
index b66b08c..17c4886 100644
--- a/cros/p2p_manager_unittest.cc
+++ b/cros/p2p_manager_unittest.cc
@@ -358,7 +358,7 @@
 
 // Check that sharing a *new* file works.
 TEST_F(P2PManagerTest, ShareFile) {
-  const int kP2PTestFileSize = 1000 * 1000;  // 1 MB
+  const int kP2PTestFileSize = 1000 * 8;  // 8 KB
 
   EXPECT_TRUE(manager_->FileShare("foo", kP2PTestFileSize));
   EXPECT_EQ(manager_->FileGetPath("foo"),
@@ -377,7 +377,7 @@
 
 // Check that making a shared file visible, does what is expected.
 TEST_F(P2PManagerTest, MakeFileVisible) {
-  const int kP2PTestFileSize = 1000 * 1000;  // 1 MB
+  const int kP2PTestFileSize = 1000 * 8;  // 8 KB
 
   // First, check that it's not visible.
   manager_->FileShare("foo", kP2PTestFileSize);