minor #18966 [console] Improve table rendering performance (aik099)

This PR was submitted for the master branch but it was merged into the 2.7 branch instead (closes #18966).

Discussion
----------

[console] Improve table rendering performance

| Q             | A
| ------------- | ---
| Branch?       | 2.8
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #18957
| License       | MIT
| Doc PR        | -

With these improvements on my application, that is rendering table with 128 rows and 5 columns I've cut off total application runtime from **0.39s** to **0.26s**.

Commits
-------

73b812e Make one call to "OutputInterface::write" method per table row

Author: fabpot

src/Symfony/Component/Console/Helper/Table.php

@@ -257,7 +257,7 @@ private function renderRowSeparator()
      */
     private function renderColumnSeparator()
     {
-        $this->output->write(sprintf($this->style->getBorderFormat(), $this->style->getVerticalBorderChar()));
+        return sprintf($this->style->getBorderFormat(), $this->style->getVerticalBorderChar());
     }
 
     /**
@@ -274,12 +274,12 @@ private function renderRow(array $row, $cellFormat)
             return;
         }
 
-        $this->renderColumnSeparator();
+        $rowContent = $this->renderColumnSeparator();
         foreach ($this->getRowColumns($row) as $column) {
-            $this->renderCell($row, $column, $cellFormat);
-            $this->renderColumnSeparator();
+            $rowContent .= $this->renderCell($row, $column, $cellFormat);
+            $rowContent .= $this->renderColumnSeparator();
         }
-        $this->output->writeln('');
+        $this->output->writeln($rowContent);
     }
 
     /**
@@ -306,12 +306,13 @@ private function renderCell(array $row, $column, $cellFormat)
         }
 
         if ($cell instanceof TableSeparator) {
-            $this->output->write(sprintf($this->style->getBorderFormat(), str_repeat($this->style->getHorizontalBorderChar(), $width)));
-        } else {
-            $width += Helper::strlen($cell) - Helper::strlenWithoutDecoration($this->output->getFormatter(), $cell);
-            $content = sprintf($this->style->getCellRowContentFormat(), $cell);
-            $this->output->write(sprintf($cellFormat, str_pad($content, $width, $this->style->getPaddingChar(), $this->style->getPadType())));
+            return sprintf($this->style->getBorderFormat(), str_repeat($this->style->getHorizontalBorderChar(), $width));
         }
+
+        $width += Helper::strlen($cell) - Helper::strlenWithoutDecoration($this->output->getFormatter(), $cell);
+        $content = sprintf($this->style->getCellRowContentFormat(), $cell);
+
+        return sprintf($cellFormat, str_pad($content, $width, $this->style->getPaddingChar(), $this->style->getPadType()));
     }
 
     /**