Reduce the amount of text to perf test for long-line-nowrap-collapse

When a perf improvements for collapsing whitespace[1] landed,
following tests were adjusted to be 12x slower, to match to the test
without whitespace collapsing.

However, these tests then timeout on reference build.

This patch defers the adjust until the reference build is updated.

PerformanceTests/Layout/long-line-nowrap-collapse.html
PerformanceTests/Layout/long-line-nowrap-spans-collapse.html

[1] https://codereview.chromium.org/2285053002

BUG=642884

Review-Url: https://codereview.chromium.org/2323213002
Cr-Commit-Position: refs/heads/master@{#417557}

third_party/WebKit/PerformanceTests/Layout/long-line-nowrap-collapse.html

@@ -15,7 +15,7 @@
 function run() {
   var test = new LineLayoutPerfTest(container);
   test.spanCount = 0;
-  test.lineCount = 10000;
+  test.lineCount = 1000;
   test.wordSeparator = '  '; // Make all word separators collapsible.
   test.run('Measures performance of "white-space: nowrap" with collapsible spaces.');
 }

third_party/WebKit/PerformanceTests/Layout/long-line-nowrap-spans-collapse.html

@@ -15,7 +15,7 @@
 function run() {
   var test = new LineLayoutPerfTest(container);
   test.spanCount = 10;
-  test.lineCount = 1000;
+  test.lineCount = 100;
   test.wordSeparator = '  '; // Make all word separators collapsible.
   test.run('Measures performance of "white-space: nowrap" with multiple spans and collapsible spaces.');
 }