Force scales 125% and lower down to 100%

125 comes from:

150% == 144 logpixels
125% == 120 logpixels
100% == 96 logpixels

R=cpu@chromium.org, sky@chromium.org, ananta@chromium.org
BUG=395425

Review URL: https://codereview.chromium.org/516743002

Cr-Commit-Position: refs/heads/master@{#292494}

ui/gfx/win/dpi.cc

@@ -134,6 +134,11 @@ Size GetDPI() {
 
 float GetDPIScale() {
   if (IsHighDPIEnabled()) {
+    if (GetDPI().width() <= 120) {
+      // 120 logical pixels is 125% scale. We do this to maintain previous
+      // (non-DPI-aware) behavior where only the font size was boosted.
+      return 1.0;
+    }
     return gfx::Display::HasForceDeviceScaleFactor() ?
         gfx::Display::GetForcedDeviceScaleFactor() :
         GetUnforcedDeviceScaleFactor();